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BCI Filter for Sea Sprite+

Daniel KK4MRN
 

Hello,
Somehow I missed where a BCI Filter (Broadcast Interference?) was mentioned that can be built for the Sea Sprite+.? I think Rex pointed out a circuit that can be built?

I could hear a AM Broadcast station on my Sea Sprite+.

Does anyone know where that BCI filter circuit was?

Would a band pass filter for 40m work like qrp-labs band pass filter kit?

73 Daniel KK4MRN


Winding my toroids

 

Now that I am back in the Rockford/Chicago area & have access to our storage, I was finally able to retrieve much of my ham stuff which was in storage due to having a 23' RV & now can bring a bit more along with our 32' RV. I have more than 16 QRPme unbuilt kits & at least 4 I built (before getting sick) along with kits I previously built from K1SWL, 4StatesQrp, QrpGuys, etc. Many kits are 1 off from the current version, some even older, some current. I will build them all. Some I robbed parts from to make up for missing parts in others, I just bought an assortment of resistors, caps, diodes, & transistors from AMZ, they come in little compact plastic bins, great for travel, so I can back-fill those borrowed parts.

?In 2016 I was stricken by sudden onset cataracts that nearly completely blinded me in both eyes & had other health issues that didn't let me have eye surgeries until 2018. I had completely lost my depth perception & soldering was a very painfully frustrating experience. During this time I had no health insurance & completely relied on my XYL & maintenance staff to be my eyes as I directed repairs & shared my infinite wisdom of knowledge nobody else cared about (sewer snaking, water line repairs, chlorine injectors, etc), except when everyone expected it to work already, lol. Anyway, today I can see better than when I was 40, so have been getting my life back together slowly. I can't retired for 6 years yet, so radio has to be part time for a while, unfortunately. At least for now.

It looks like I have to wind a ton of toroids & we all seen Rex's videos on toroid winding, I have watched it many times & used it to build my 1:49 multiband antennas. This article uses very familiar tools!

https://qrper.com/2023/04/video-alans-method-for-winding-toroids/

Cheers es 72, Davey - KU9L


Re: Photo of my Sea Sprite+ in my ham shack

 

On Mon, Apr 3, 2023 at 01:32 AM, Daniel KK4MRN wrote:
Did you try to make any contacts with other Sea Sprites on 7110 on the weekend of March 25th or last weekend?? What about this upcoming weekend?
Didn't know was supposed to, didn't realize that there was a "Sprite Sprint" happening.? Mine is on 20M anyway so can't run it on 40M anymore.? I have a "Lil Squall" that has band modules for 80, 40, 30, 20, 15 though.? About the same radio in a smaller can.? Ordered a 10M module but have yet to receive it.

I had no issues with building the Sprite, mine was built awhile ago.? in Summer of 2016 was first QSO to KS.? As far as I recall, have never made contact with another Sprite.? Not even with W5USJ who isn't far from me.? Have had QSO with him using a Lil Squall in 2016.

Curt KB5JO


Re: Photo of my Sea Sprite+ in my ham shack

Daniel KK4MRN
 

Curt,
Nice.? Did you try to make any contacts with other Sea Sprites on 7110 on the weekend of March 25th or last weekend?? What about this upcoming weekend?

I encourage others to post notes, photos, or links to YouTube videos they did of their Sea Sprite+.

Did anyone have issues building or operating?

Did anyone get on the air?

Did anyone make contacts?

Other hams would like to know.

73 Daniel KK4MRN


Re: Rockmite kit build

Daniel KK4MRN
 

Russel and John,
Thanks for the feedback.

I think I will get a RockMite.? But I do not have to stick with 40m.? Hmmm...? Maybe 80, 30, or 20m.? I think 30m is special for CW because no voice modes are allowed.??
I am eyeing the Lil Squall though.? And am thinking of the Sudden Receiver too.? ? However, to use a Two Tinned Tuna with a Sudden Receiver, I would need a T/R switch/Mute circuits; there is a can kit for the T/R switch.? And a can for power distribution but the amp needs its own power supply.

Usually, I have no interest in RF amps, but I think an amp to bring up a QRPp radio to QRP would be good to have.??

I bought the Kindle version of the book Electronic Principles - Malvino.? ?Good quality technical books cost money.? And I looked at the preview on Amazon so that is what convinced me to get it.? Most of my books I get these days are Kindle books.? However, my Experimental Methods in RF Design is a softcopy.? ?I also have Grob's Basic Electronics which so far looks like a good supplement to Electronics of Radio.? However, I typically read the books on my ipad or my Windows 10 PC with 27" monitor.

Any good books on troubleshooting?

73 Daniel KK4MRN


Re: Rockmite kit build --> Tunah Storms

 

I am inventorying my Tuna Tunah Kit again, but have to go finish packing up the RV. After we pull out of our site tomorrow & get on the straight & level I have to spend an hour or so adjusting our new hitch so when I step on the brakes both front and real axles maintain the same expected weight distribution.

Speaking of storms, it is the reason spring travel is so risky. In 2020 we had $6,300 in hail damage to our truck when traveling through Nebraska. We leave central FL tomorrow, however, won't be in IL until Tuesday when there again is a good chance of strong storms. The fact that we delayed leaving FL yesterday meant everything is a calculated risk, LOL. We travel up I-39 to Rockford as there are no local state parks in the Chicago area, but I-90 is a pretty good road to get to W. Dundee afterward. :-) Davey - KU9L

On Friday, March 31, 2023 at 08:31:49 PM EDT, John Putnum, AC9UV <johnfputnam@...> wrote:


Davey,

Rockford has a tornado warning tonight and high winds. The whole area has a squal line going through. I hope those in Rockford are going to be OK.

---John AC9UV

? ? ?73

On 03/31/2023 12:22 PM David Knapp via groups.io <renewables@...> wrote:



There is the new 10M version coming out shortly as well, looking forward to it!!!

I know I have several kits not received that will be chasing me across the country as we work our way north to Chicago starting on Sunday. We delayed leaving a couple of days because the TORCON level where we are headed is a 9 today, gulp!!!

My Sea Sprinte will have to get assembled in Rockford, IL when Nani is with the grandbabies and I have slipped back to the RV for a little POTA activation and to make some solder smoke.

What was the bandwidth like at the receiver? I have a 200Hz audio filter I have to build yet, so many kits, so little time. I figure I can't die until I run out of kits to build.

My latest project is in use today, my new Molex connector just came from AMZ:?



I'll check back in a few days Daniel and John!

Davey - KU9L


On Friday, March 31, 2023 at 01:03:12 PM EDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

Davey,

Rockford has a tornado warning tonight and high winds. The whole area has a squal line going through. I hope those in Rockford are going to be OK.

---John AC9UV

? ? ?73

On 03/31/2023 12:22 PM David Knapp via groups.io <renewables@...> wrote:



There is the new 10M version coming out shortly as well, looking forward to it!!!

I know I have several kits not received that will be chasing me across the country as we work our way north to Chicago starting on Sunday. We delayed leaving a couple of days because the TORCON level where we are headed is a 9 today, gulp!!!

My Sea Sprinte will have to get assembled in Rockford, IL when Nani is with the grandbabies and I have slipped back to the RV for a little POTA activation and to make some solder smoke.

What was the bandwidth like at the receiver? I have a 200Hz audio filter I have to build yet, so many kits, so little time. I figure I can't die until I run out of kits to build.

My latest project is in use today, my new Molex connector just came from AMZ:?



I'll check back in a few days Daniel and John!

Davey - KU9L


On Friday, March 31, 2023 at 01:03:12 PM EDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

Russell,

? Done, thanks.

---John AC9UV

On 03/31/2023 4:31 PM Russell Smith via groups.io <n0qlt@...> wrote:


OUCH! My wallet hurts just looking at that.

I think my copy is second edition. I bought it on a work trip when I was somewhere that had a Borders or Barnes & Noble It was like $75 or something back in 2000. My original copy got damaged in the tornado in 2011. I think I found another copy on ebay or Better World/Thrift Books/Goodwill for $5-$10, but that was in 2011.? I really want the 3rd, but I'm not ready to let go of the cash yet. For most of our purposes, the 1st or 2nd has some good information of historical interest.? Paul Horowitz is a Ham, I believe (or was licensed at one time).


Here's one copy of Mavino. Just about any edition is fine:



-HRS


H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 04:24:11 PM CDT, John Putnum, AC9UV <johnfputnam@...> wrote:


Russell,

I found this entry on Amazon for one of the books.


Seems like it is a valued book. I have seen prices down to 9.50 for used 1989 copy.

? ?---John AC9UV

On 03/31/2023 4:01 PM Russell Smith via groups.io <n0qlt@...> wrote:


Daniel,?

Two books that you should have in your bookshelf in addition to EMRFD and SSD are The Art of Electronics by Horowitz and Hill and Malvino's Electronic Principles. You can get good used copies for like $5.? I have a bunch of texts I used when I was getting my undergrad electrical engineering degree. Those were not ever called out for any of my classes, but I used them more than most.? Definitely worth the money.

-HRS

H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 12:03:12 PM CDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

OUCH! My wallet hurts just looking at that.

I think my copy is second edition. I bought it on a work trip when I was somewhere that had a Borders or Barnes & Noble It was like $75 or something back in 2000. My original copy got damaged in the tornado in 2011. I think I found another copy on ebay or Better World/Thrift Books/Goodwill for $5-$10, but that was in 2011.? I really want the 3rd, but I'm not ready to let go of the cash yet. For most of our purposes, the 1st or 2nd has some good information of historical interest.? Paul Horowitz is a Ham, I believe (or was licensed at one time).


Here's one copy of Mavino. Just about any edition is fine:



-HRS


H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 04:24:11 PM CDT, John Putnum, AC9UV <johnfputnam@...> wrote:


Russell,

I found this entry on Amazon for one of the books.


Seems like it is a valued book. I have seen prices down to 9.50 for used 1989 copy.

? ?---John AC9UV

On 03/31/2023 4:01 PM Russell Smith via groups.io <n0qlt@...> wrote:


Daniel,?

Two books that you should have in your bookshelf in addition to EMRFD and SSD are The Art of Electronics by Horowitz and Hill and Malvino's Electronic Principles. You can get good used copies for like $5.? I have a bunch of texts I used when I was getting my undergrad electrical engineering degree. Those were not ever called out for any of my classes, but I used them more than most.? Definitely worth the money.

-HRS

H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 12:03:12 PM CDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

Russell,

I found this entry on Amazon for one of the books.


Seems like it is a valued book. I have seen prices down to 9.50 for used 1989 copy.

? ?---John AC9UV

On 03/31/2023 4:01 PM Russell Smith via groups.io <n0qlt@...> wrote:


Daniel,?

Two books that you should have in your bookshelf in addition to EMRFD and SSD are The Art of Electronics by Horowitz and Hill and Malvino's Electronic Principles. You can get good used copies for like $5.? I have a bunch of texts I used when I was getting my undergrad electrical engineering degree. Those were not ever called out for any of my classes, but I used them more than most.? Definitely worth the money.

-HRS

H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 12:03:12 PM CDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

Daniel,?

Two books that you should have in your bookshelf in addition to EMRFD and SSD are The Art of Electronics by Horowitz and Hill and Malvino's Electronic Principles. You can get good used copies for like $5.? I have a bunch of texts I used when I was getting my undergrad electrical engineering degree. Those were not ever called out for any of my classes, but I used them more than most.? Definitely worth the money.

-HRS

H. Russell Smith, N0QLT??? ?????????????????????????????


On Friday, March 31, 2023 at 12:03:12 PM CDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

Daniel,

The RockMite kits (40 meter) from QRPMe

SPECIFICATIONS:

- Double-sided PCB 2.0" x 2.5", plated-thru-holes, solder masked & silk screened for easy assembly
-?SAME size and mounting holes as the original so MINT TIN FRIENDLY
- 0.5W power output at 13V supply
- Supply voltage range 12-15V
- AVAILABLE FREQUENCIES:
80m will be shipped with a PAIR of 3550 & 3560 cyrstals
40m will be shipped with 7030 & 7040
30m will be shipped with 10106 & 10116
20m kits will be shipped with 14050 & 14060 crystals

- Automatic T/R offset, reversible
- Built-in custom version of Ham Gadgets PicoKeyer-RM Iambic keyer, 5-40 WPM
- Built in side tone, approx. 700Hz
- Includes assembly instructions and operating tips
-?ALL on-board parts, input/output connectors and wiring to connect them together are supplied in the Rockmite ][ kit
-?ALL parts for the keyer SPEED, audio VOLUME and power ON/OFF switch & LED mods are also NOW included

TOTAL parts kit PRICE of $50

It has a built in keyer, is a transeiver,? crystal controlled , half watt. The keyer menu is done by button pushes and paddle clicks with cw responses which requires the menu close at hand so you know how to navigate, but with the enclosure you have a speed pot which the thing you want to set most outside the menu. So a lot of features in a small package for a good price.?

The build is relatively straight forward but not a step by step, just read it and if you are getting the power mod (do that first) read all before. There is one resistor that is speed control but you don't put that in and run wires out to the pot on the enclosure, so a few things to watch out for.

So your coming through Chicago?? I live immediately west of Chicago (bordering) in Oak Park. if your going to Rockford you probably will tak the JFK towards Ohare, but the segment just north of the Loop is under some construction and a better route might be to take I290 which goes right through Oak Park.? Let me know and you can stop by and see my meger antenna farm.

? ?---John AC9UV

? ? ? 73

On 03/31/2023 12:22 PM David Knapp via groups.io <renewables@...> wrote:



There is the new 10M version coming out shortly as well, looking forward to it!!!

I know I have several kits not received that will be chasing me across the country as we work our way north to Chicago starting on Sunday. We delayed leaving a couple of days because the TORCON level where we are headed is a 9 today, gulp!!!

My Sea Sprinte will have to get assembled in Rockford, IL when Nani is with the grandbabies and I have slipped back to the RV for a little POTA activation and to make some solder smoke.

What was the bandwidth like at the receiver? I have a 200Hz audio filter I have to build yet, so many kits, so little time. I figure I can't die until I run out of kits to build.

My latest project is in use today, my new Molex connector just came from AMZ:?



I'll check back in a few days Daniel and John!

Davey - KU9L


On Friday, March 31, 2023 at 01:03:12 PM EDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

 

There is the new 10M version coming out shortly as well, looking forward to it!!!

I know I have several kits not received that will be chasing me across the country as we work our way north to Chicago starting on Sunday. We delayed leaving a couple of days because the TORCON level where we are headed is a 9 today, gulp!!!

My Sea Sprinte will have to get assembled in Rockford, IL when Nani is with the grandbabies and I have slipped back to the RV for a little POTA activation and to make some solder smoke.

What was the bandwidth like at the receiver? I have a 200Hz audio filter I have to build yet, so many kits, so little time. I figure I can't die until I run out of kits to build.

My latest project is in use today, my new Molex connector just came from AMZ:?



I'll check back in a few days Daniel and John!

Davey - KU9L


On Friday, March 31, 2023 at 01:03:12 PM EDT, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Re: Rockmite kit build

Daniel KK4MRN
 

John,

I like the photos of your RockMite.

Is the QRPme's RockMite ][ CW Transceiver good for someone who has built a Sea Sprite from QRPme?

I am looking into building another radio once I've done all the mods to the Sea Sprite, etc.

My build of the Sea Sprite+ was a success.? And the only mods I have done are the 3rd pin for the crystal and the bypass for the antenna.? ?For the crystal, I simply took a discarded resistor lead and used that for the 3rd pin of the crystal.? No need to cause harm to an innocent crystal... LOL

I am no expert nor beginner, but there have been kits or homebrewing in the past where I failed.? I have 3 kit projects from various places that I have failed and eventually will try fix them.? So, I was happy I built the Sea Sprite radio and it worked.

I think understanding how to diagnose why a radio is not working and how to fix it is an acquired skill set via lots of experience building and fixing kits and homebrewing.? I have not gotten there yet.? Do you suggest a book to read to help fix radio electronics???

73 Daniel KK4MRN


Rockmite kit build

 

¿ªÔÆÌåÓý

Group,

With all that time on my hands after the buildathon I pieced together a Rockmite ][ 20m kit I had waiting in the wings for about 2 years.? I almost got it done but am waiting for a Power Mod kit from Rex.

I have the 30 and 40 Rockmites already built so just filling in gaps.

Not a kit for a very beginner as the build instructions are small but well marked, but then the band specific part and the band mods and the enclosure are perterbations on the straight build and a little scattered. Read before building is always best.

? ?---John AC9UV

? ? ? 73


Re: Revisiting the Tuna Power System kit TPS

 

Today the 12 AH battery performed the same exact way, the LIFEPO4 battery BMS disconnects when it becomes full and the battery voltage becomes too high or is about to be overcharged.? No issues on my end, had I been using a radio, charging my cell phone (for HAMRS logger app), and other Two Tinned Tuna devices the small solar panel would have just extended my operating time rather than just filling up the battery.

Next, I will finish the Tuna Tunah project I already started. I think I assembled one in 2018 already, but it is in storage in Chicago.

Does anyone have a source for the mating Molex 4-pin connecter on the Tuna Power System Kit?? The first three I bought are too small or the wrong shape, do not rely on the photos on Amazon to be the exact item you need, just saying. I think the version I need might be related to computer floppy drive connector sizes, but I just want the mating connector with female pins so I can power my Penntek TR-35 QRP 4-band radio via the TPS kit. I need to power it and the Molex connector looked to be very convenient.

Davey - KU9L



On Tuesday, March 28, 2023 at 09:02:12 PM EDT, David Knapp via groups.io <renewables@...> wrote:


Additional notes:

As the datasheet shows, the Overcharge RED LED glows when the voltage reaches 14.0 volts, but charging continues until the battery reaches 14.7 volts upon which the charge current tapers off. I think the RUB of me using a LIFEPO4 lithium battery is that the battery BMS charging will shut down the ability to charge typically above 14.6 volts which is why I suddenly saw ~20 volts from the battery reading. This may have confused the 3906N IC which was to start tapering off the charge current prior to going into the 3rd stage, Float at 13.9 volts. Tomorrow I will test this with my 12AH Explorer battery box to see if I get a similar result as I did with my single 6AH battery. Now that I know the states the datasheet targets I can better determine if it meets the specs. Generally, though, my LIFEPO4 solar charge controller may be a better option. I plan to use the TPS Kit stand-alone for POTA and charge the batteries separately.

I noticed zero hum when using a tuna project from my batteries compared to the wall wart that makes tons of hum.

Davey - KU9L

Here is the info from the Data Sheet:

This?charger circuit diagram?is based on the?UC3906 battery charger controller?that contains all of the necessary circuitry to control the charge and hold cycle for sealed lead-acid batteries. The UC3906 battery charger circuit is specifically designed to provide the proper charging voltage and current determined by the temperature and state of charge of the battery.
The UC3906 battery charger circuit controller monitor and control both the output voltage and current of the charger through three separate charge states .
UC3906? has separate voltage loop and current limit amplifiers which regulate the output voltage and current levels in the charger by controlling the onboard driver.The charger circuit requires 18 to 22 volts DC input.? Three optical ( LED ) indicators show the charge state .? The UC3906 IC is configured to provide three charge states:
Bulk charge ¨C the charger operates in a constant-current charge mode until the battery reaches the programmed full-charge voltage.

Overcharge ¨C when the voltage reaches the programmed full-charge voltage, the charger switches to overcharge mode to ¡®top-off¡¯ the battery.
Float charge ¨C when the current decreases to the minimum overcharge current, the charger enters the float charge mode.
Voltage and current sense comparators are used to sense the battery condition and respond with logic inputs to the charge state logic.
How works these three states modes ?

If the battery voltage is between 10.2 and 12.2 volts? ( when charger is connected to the battery )? charging begins at the programmed bulk charge current and continues until the voltage rises to 14.0 volts. In this state mode only the power LED is illuminated .
When the voltage exceeds 14.0 volts, the overcharge LED illuminates (charger has entered in the overcharge mode) and charging continues. The charge current remains at the programmed bulk charge rate until the battery voltage reaches 14.7 volts.
When the battery voltage reaches 14.7 volts, the charging current begins to taper off.
When it decreases to 1/10 ?of the bulk charge current, the overcharge LED extinguishes and the float LED illuminates to indicate that the charger has entered the float charge mode (voltage is maintained at 13.9 volts ). ?The TIP transistor must be mounted on a heatsink , to prevent the damage of it cause of high temperature .



On Tuesday, March 28, 2023 at 07:38:00 PM EDT, David Knapp via groups.io <renewables@...> wrote:


Now that we have stable power at the campground again and I needed to finish up my projects as we are leaving FL this weekend, I decided to finish up my Tuna Power System Kit.

This kit is a central power distribution kit for all of my tuna can kits, it also will charge a sealed lead acid (SLA) battery with an 18-20 volt charging input. The kit is set up for wall warts outputting from 0.4 - 1.0 charging amps.

I don't follow instructions well, ask my teachers from grade school! I believe in populating data points wherever I can. Assembly was halted because I was missing three 1K ohm resistors out of four the kit claimed to need. Because our campground had no power for 36 hours and no internet, I could not attend the Buildathon live. However, after the power came back on and then became stable (they doubled the size of the transformer), I decided to finish my TPS kit.

I bought a box of Diodes, 1/4w, 1/2w, & 2w resistors assortment to cover for those missing parts. In my case, I was missing three 1K ohm 1/4w metal film resistors but was given three 3.3K ohm resistors by accident. In this case, I calculated that those would not work in the place of the missing parts.

Anyway, I finished the assembly and even made a couple of mods to add a digital voltmeter at both the Battery input and the solar input so I could determine charging potential.

I went to buy an SLA battery but found a cheap Chinese 6ah LIFEPO4 lithium battery instead. I wondered if it could be used in the TPS kit.

I plugged it in and the TPS kit sprung to life with 13.3 volts of output. I then plugged in a 20-watt solar panel that claims 20 volts open circuit and 18 volts at full 1.0 amp output!!!!? Since this was a little higher than Rex or Chuck intended (0.7 amp max), I removed the 1n4004 1.0 amp rectifier and replaced it with a 3.0-amp 1N5404 diode instead. The 20-watt solar panel sprung to life at 17.5-volts and with whispy clouds, I was measuring between 0.7 - 1.0 amps via my amp clamp meter on the solar plus input.

The green LED illuminated to show charging and the battery voltage slowly began rising. Once it got to 13.8 volts I thought, "Well, the charge regulation should kick in now!" But it didn't, it continued to climb to 14.0 volts, 14.1, 14.3, 14.5, and 14.6 volts ... whew! Suddenly it jumped to 20.5 volts!!!! Oh my!!!

Why is this? Well, the battery voltage continued to hover around 14.6 volts, but the BMS (Battery Management System)? detects the higher voltage that the charging circuit tries to ramp up to and it disconnects the charging to protect itself. The battery still provides a 14.6-volt output, but the charging circuit with a near-zero amperage sees an open circuit that matches the voltage input from the solar panel.

Now, this would not be good for a radio's sensitive input voltage, but since it was an open circuit voltage I put a load on it and the voltage came right down. I am not sure why the UC3906N IC circuit did not limit itself to 13.8 volts since that is what I would expect with an SLA battery. I moved the TPS kit over to the Explorer battery box that I did a video on and tomorrow I will repeat my experiment to see what happens when the 12AH of LIFEPO4 batteries are near full charge. Tonight the voltage only rose to 13.5 volts as the batteries were chugging along all day powering my 30-watt 12-volt DC soldering iron. I triple-checked my TPS kit and verified all resistors, two capacitors, IC, and voltage regulators were installed correctly and at the proper values. So aside from the 13.8-volt regulation voltage, I declare the kit to be a success.?

I have a 24-amp MPPT solar charge controller that I charge my Explorer box with so I don't really need the charging circuit of the TPS kit, but I did try out the USB charging circuit and it worked perfectly. I left my fingerprints?
on the VR1 heatsink as I was charging my Android phone on it, a load that was not in the design criteria I am sure ... but it worked magically!

Anyway, back to soldering. When I get to Illinois on April 4th I will start on my Sea Sprinte so my grandkids can see what Popi builds when I am off by myself!

Cheers,

Davey - KU9L


Inline image





Re: Revisiting the Tuna Power System kit TPS

 

Additional notes:

As the datasheet shows, the Overcharge RED LED glows when the voltage reaches 14.0 volts, but charging continues until the battery reaches 14.7 volts upon which the charge current tapers off. I think the RUB of me using a LIFEPO4 lithium battery is that the battery BMS charging will shut down the ability to charge typically above 14.6 volts which is why I suddenly saw ~20 volts from the battery reading. This may have confused the 3906N IC which was to start tapering off the charge current prior to going into the 3rd stage, Float at 13.9 volts. Tomorrow I will test this with my 12AH Explorer battery box to see if I get a similar result as I did with my single 6AH battery. Now that I know the states the datasheet targets I can better determine if it meets the specs. Generally, though, my LIFEPO4 solar charge controller may be a better option. I plan to use the TPS Kit stand-alone for POTA and charge the batteries separately.

I noticed zero hum when using a tuna project from my batteries compared to the wall wart that makes tons of hum.

Davey - KU9L

Here is the info from the Data Sheet:

This?charger circuit diagram?is based on the?UC3906 battery charger controller?that contains all of the necessary circuitry to control the charge and hold cycle for sealed lead-acid batteries. The UC3906 battery charger circuit is specifically designed to provide the proper charging voltage and current determined by the temperature and state of charge of the battery.
The UC3906 battery charger circuit controller monitor and control both the output voltage and current of the charger through three separate charge states .
UC3906? has separate voltage loop and current limit amplifiers which regulate the output voltage and current levels in the charger by controlling the onboard driver.The charger circuit requires 18 to 22 volts DC input.? Three optical ( LED ) indicators show the charge state .? The UC3906 IC is configured to provide three charge states:
Bulk charge ¨C the charger operates in a constant-current charge mode until the battery reaches the programmed full-charge voltage.

Overcharge ¨C when the voltage reaches the programmed full-charge voltage, the charger switches to overcharge mode to ¡®top-off¡¯ the battery.
Float charge ¨C when the current decreases to the minimum overcharge current, the charger enters the float charge mode.
Voltage and current sense comparators are used to sense the battery condition and respond with logic inputs to the charge state logic.
How works these three states modes ?

If the battery voltage is between 10.2 and 12.2 volts? ( when charger is connected to the battery )? charging begins at the programmed bulk charge current and continues until the voltage rises to 14.0 volts. In this state mode only the power LED is illuminated .
When the voltage exceeds 14.0 volts, the overcharge LED illuminates (charger has entered in the overcharge mode) and charging continues. The charge current remains at the programmed bulk charge rate until the battery voltage reaches 14.7 volts.
When the battery voltage reaches 14.7 volts, the charging current begins to taper off.
When it decreases to 1/10 ?of the bulk charge current, the overcharge LED extinguishes and the float LED illuminates to indicate that the charger has entered the float charge mode (voltage is maintained at 13.9 volts ). ?The TIP transistor must be mounted on a heatsink , to prevent the damage of it cause of high temperature .



On Tuesday, March 28, 2023 at 07:38:00 PM EDT, David Knapp via groups.io <renewables@...> wrote:


Now that we have stable power at the campground again and I needed to finish up my projects as we are leaving FL this weekend, I decided to finish up my Tuna Power System Kit.

This kit is a central power distribution kit for all of my tuna can kits, it also will charge a sealed lead acid (SLA) battery with an 18-20 volt charging input. The kit is set up for wall warts outputting from 0.4 - 1.0 charging amps.

I don't follow instructions well, ask my teachers from grade school! I believe in populating data points wherever I can. Assembly was halted because I was missing three 1K ohm resistors out of four the kit claimed to need. Because our campground had no power for 36 hours and no internet, I could not attend the Buildathon live. However, after the power came back on and then became stable (they doubled the size of the transformer), I decided to finish my TPS kit.

I bought a box of Diodes, 1/4w, 1/2w, & 2w resistors assortment to cover for those missing parts. In my case, I was missing three 1K ohm 1/4w metal film resistors but was given three 3.3K ohm resistors by accident. In this case, I calculated that those would not work in the place of the missing parts.

Anyway, I finished the assembly and even made a couple of mods to add a digital voltmeter at both the Battery input and the solar input so I could determine charging potential.

I went to buy an SLA battery but found a cheap Chinese 6ah LIFEPO4 lithium battery instead. I wondered if it could be used in the TPS kit.

I plugged it in and the TPS kit sprung to life with 13.3 volts of output. I then plugged in a 20-watt solar panel that claims 20 volts open circuit and 18 volts at full 1.0 amp output!!!!? Since this was a little higher than Rex or Chuck intended (0.7 amp max), I removed the 1n4004 1.0 amp rectifier and replaced it with a 3.0-amp 1N5404 diode instead. The 20-watt solar panel sprung to life at 17.5-volts and with whispy clouds, I was measuring between 0.7 - 1.0 amps via my amp clamp meter on the solar plus input.

The green LED illuminated to show charging and the battery voltage slowly began rising. Once it got to 13.8 volts I thought, "Well, the charge regulation should kick in now!" But it didn't, it continued to climb to 14.0 volts, 14.1, 14.3, 14.5, and 14.6 volts ... whew! Suddenly it jumped to 20.5 volts!!!! Oh my!!!

Why is this? Well, the battery voltage continued to hover around 14.6 volts, but the BMS (Battery Management System)? detects the higher voltage that the charging circuit tries to ramp up to and it disconnects the charging to protect itself. The battery still provides a 14.6-volt output, but the charging circuit with a near-zero amperage sees an open circuit that matches the voltage input from the solar panel.

Now, this would not be good for a radio's sensitive input voltage, but since it was an open circuit voltage I put a load on it and the voltage came right down. I am not sure why the UC3906N IC circuit did not limit itself to 13.8 volts since that is what I would expect with an SLA battery. I moved the TPS kit over to the Explorer battery box that I did a video on and tomorrow I will repeat my experiment to see what happens when the 12AH of LIFEPO4 batteries are near full charge. Tonight the voltage only rose to 13.5 volts as the batteries were chugging along all day powering my 30-watt 12-volt DC soldering iron. I triple-checked my TPS kit and verified all resistors, two capacitors, IC, and voltage regulators were installed correctly and at the proper values. So aside from the 13.8-volt regulation voltage, I declare the kit to be a success.?

I have a 24-amp MPPT solar charge controller that I charge my Explorer box with so I don't really need the charging circuit of the TPS kit, but I did try out the USB charging circuit and it worked perfectly. I left my fingerprints?
on the VR1 heatsink as I was charging my Android phone on it, a load that was not in the design criteria I am sure ... but it worked magically!

Anyway, back to soldering. When I get to Illinois on April 4th I will start on my Sea Sprinte so my grandkids can see what Popi builds when I am off by myself!

Cheers,

Davey - KU9L


Inline image





Revisiting the Tuna Power System kit TPS

 

Now that we have stable power at the campground again and I needed to finish up my projects as we are leaving FL this weekend, I decided to finish up my Tuna Power System Kit.

This kit is a central power distribution kit for all of my tuna can kits, it also will charge a sealed lead acid (SLA) battery with an 18-20 volt charging input. The kit is set up for wall warts outputting from 0.4 - 1.0 charging amps.

I don't follow instructions well, ask my teachers from grade school! I believe in populating data points wherever I can. Assembly was halted because I was missing three 1K ohm resistors out of four the kit claimed to need. Because our campground had no power for 36 hours and no internet, I could not attend the Buildathon live. However, after the power came back on and then became stable (they doubled the size of the transformer), I decided to finish my TPS kit.

I bought a box of Diodes, 1/4w, 1/2w, & 2w resistors assortment to cover for those missing parts. In my case, I was missing three 1K ohm 1/4w metal film resistors but was given three 3.3K ohm resistors by accident. In this case, I calculated that those would not work in the place of the missing parts.

Anyway, I finished the assembly and even made a couple of mods to add a digital voltmeter at both the Battery input and the solar input so I could determine charging potential.

I went to buy an SLA battery but found a cheap Chinese 6ah LIFEPO4 lithium battery instead. I wondered if it could be used in the TPS kit.

I plugged it in and the TPS kit sprung to life with 13.3 volts of output. I then plugged in a 20-watt solar panel that claims 20 volts open circuit and 18 volts at full 1.0 amp output!!!!? Since this was a little higher than Rex or Chuck intended (0.7 amp max), I removed the 1n4004 1.0 amp rectifier and replaced it with a 3.0-amp 1N5404 diode instead. The 20-watt solar panel sprung to life at 17.5-volts and with whispy clouds, I was measuring between 0.7 - 1.0 amps via my amp clamp meter on the solar plus input.

The green LED illuminated to show charging and the battery voltage slowly began rising. Once it got to 13.8 volts I thought, "Well, the charge regulation should kick in now!" But it didn't, it continued to climb to 14.0 volts, 14.1, 14.3, 14.5, and 14.6 volts ... whew! Suddenly it jumped to 20.5 volts!!!! Oh my!!!

Why is this? Well, the battery voltage continued to hover around 14.6 volts, but the BMS (Battery Management System)? detects the higher voltage that the charging circuit tries to ramp up to and it disconnects the charging to protect itself. The battery still provides a 14.6-volt output, but the charging circuit with a near-zero amperage sees an open circuit that matches the voltage input from the solar panel.

Now, this would not be good for a radio's sensitive input voltage, but since it was an open circuit voltage I put a load on it and the voltage came right down. I am not sure why the UC3906N IC circuit did not limit itself to 13.8 volts since that is what I would expect with an SLA battery. I moved the TPS kit over to the Explorer battery box that I did a video on and tomorrow I will repeat my experiment to see what happens when the 12AH of LIFEPO4 batteries are near full charge. Tonight the voltage only rose to 13.5 volts as the batteries were chugging along all day powering my 30-watt 12-volt DC soldering iron. I triple-checked my TPS kit and verified all resistors, two capacitors, IC, and voltage regulators were installed correctly and at the proper values. So aside from the 13.8-volt regulation voltage, I declare the kit to be a success.?

I have a 24-amp MPPT solar charge controller that I charge my Explorer box with so I don't really need the charging circuit of the TPS kit, but I did try out the USB charging circuit and it worked perfectly. I left my fingerprints?
on the VR1 heatsink as I was charging my Android phone on it, a load that was not in the design criteria I am sure ... but it worked magically!

Anyway, back to soldering. When I get to Illinois on April 4th I will start on my Sea Sprinte so my grandkids can see what Popi builds when I am off by myself!

Cheers,

Davey - KU9L


Inline image





Re: Photo of my Sea Sprite+ in my ham shack

 

Well, mine is a Version 2.0 not a 6.0.? Built sometime ago.? And converted to 20M later.? You will enjoy the Sprite I think.

Curt KB5JO


Re: After Building a Two Tinned Tunas EZ Build, what next?

 

Daniel,

My first QRPMe kit was recommended by another rock climber and QRPist that liked the (I think it was) Sudden Storm radios that turned into the Rockmite ][ radios.

If you get it with the enclosure it is a nice stable rugged unit with good characteristics. Then there is the z match tuner and the rock topper to bost things and you have a cluster of boxes that work together. But each model is tuned for a band and and the rock topper needs band modules for each band (pesky screws to open it up to change band modules). But the enclosures make it easier to transport without fear of damage. But if you are just in the shack then the tuna tin radios are fine.

I have? a (Tr)uSDX that allows QRP SSB and cw and am and fm in a small package with about 4-5 watts which is another interesting route. Careful of imitations and knock offs. Check the web site for approved suppliers. A little hight price point but not out of range.

? ?Keep on Haming

? ?---John AC9UV

? 73

On 03/26/2023 6:01 PM Daniel KK4MRN via groups.io <sqldan2000@...> wrote:


Hello,
I recently built the Sea Sprite+ for the Buildathon on March 25, 2023.? It works.? It was fun!? And I plan on making mods to improve the radio.??
What QRPme kit would any of you reading this group recommend next?

Sudden Receiver ?
Rock Mite ][ transceiver ?
Super Tin Tuna 5W transmitter?
Lil Squall Transceiver ?
regular Sea Sprite transceiver?
Something else?

73 Daniel KK4MRN

On Mon, Feb 27, 2023 at 11:25 AM, Daniel KK4MRN wrote:
Hello fans of the can,
What would be a good QRPme radio kit to build next?