Re: Ordered my March 2023 Buildathon's updated Sea Sprite+ kit with coupler, key, and Zepp - I have comments and questions
Hello John, I am learning via Long Island CW Club.? I recommend the club for CW newbies.? They have 1-hour zoom meetings where you can see and hear other hams - CW students - learning the code.? And the LICW Club has changed things around.? Now, they concentrate on 12WPM instead of 20WPM. And they have a carousel that you can start at anytime. They did some research on what the original Koche scientific studies back in the early to mid 1900s.??
There is one very fast ham who can send and receive code with his brain very quickly - and he will tell you - it does not matter how fast or slow you go - who cares - if you know all your letters and digits, just get on the air...? It was Chuck Adams.? It is not necessary to do 20+ WPM these days. If you can, great.? If not, no worries. However, I do hope that hams QRS (slow code) for this event though.
Sadly, I have been doing this off and on for many years.? Hopefully it will stick with me this time via LICWC.
Did you use the Si5351A synthesizer chip for the DDS?
73 Daniel KK4MRN
On Friday, February 17, 2023 at 11:19:14 AM EST, John Putnum, AC9UV <johnfputnam@...> wrote:
Daniel,
I built the Sea Sprite a few weeks ago. Nice build, clean harmonics. Power about .54w as measured on one of my wattmeters.
I have register for the buildathon and ordered the kit.
I will have to see if I am confident with my code recognition to get on the air then.
I have not built the Lil Squall transiever but have built a couple of pixies and several Rockmite ][ and the topper. I have a 20m Rockmite kit waiting in a box for some time.
I modified one pixie to replace the crystal with a vfo that I put together from a nano ,a DDS chip, a display, and a rotary encoder. Worked nicely. I use the vfo as a frequency standard for my projects.
The pixie kits I have built have marginally acceptable harmonics. They need a LPF added to clean that up I think.?
Buildathons can be hectic. Depends on how fast you go. Rex moves right along and my problem sometimes I get a little behind, or my wife interrupts me... Doing it ahead of time can be done but the buildathon experience is different. In any case with Rex you always learn something new and useful about tools, tool use, or build techniques. In some cases how to fix problems you just caused. A great time is had by all.
? ?Enjoy,
---John AC9UV
On 02/17/2023 5:26 AM Daniel KK4MRN via groups.io <sqldan2000@...> wrote:
Hello,
By the way, I ordered the March 2023 Buildathon's Sea Sprite+ kit.? ?I still need to register for the event though.
I have some comments and questions on down.
lt
Has anybody else ordered this kit?
Anybody else participating in the Buildathon?
Anybody else getting on 7110 the weekend of March 25th and 26th?
Anybody build a QRPme Sea Sprite transceiver or QRPme Lil Squall Transceiver in the past or building one now?
Or even a Pixie transceiver?
The March 2023 Buildathon is a virtual online event.
But, if you're in Los Angeles, California, you can go in person - I think.
March 2023 Buildathon's Sea Sprite+ kit
Includes built-in antenna coupler.?
Additional items are a key and enough wire to construct a 1/2 wave End Fed Zepp antenna.
Good for a new Technician ham to build and Get On The Air.? All they need is a battery and a pair of headphones.
According to the web page, the kit's boards are on order.? So, it will take awhile for Rex to get them, then he has to put on his superman cape and turn out a bunch of kits and mail them in advance of March 25th...? I look forward to building the Sea Sprite+ and getting on the air.? ?I do suggest that anyone participating QRS (slow code) for newbies.? And hopefully I can make a few contacts - well, I hope at least one confirmed contact - with this radio especially the weekend of the Buildathon.? But more contacts the merrier.? ?Let's just make it a week long - weekend to weekend - so others who did not make a contact can keep trying.? Sometimes conditions improve.? ?So, I will be listening.? I will keep the radio on.... And if nobody pounces, I will pounce.
Would it be bad to go ahead and build SST+ kit and try it on the air before March 25th if I get it before the 25th?? Thoughts?
Map of Sea Sprite+ Builders signed up for 3/25 Buildathon
SST+ Version 6 Board layout
SST+ Version 6 Schematic
Presentation at the Buildathon on Saturday March 25th, at 10:00 PDT (1800 UTC)
2-hour session
Build a Simple Station and GOTA (Get On The Air!)
Speaker: Rex Harper W1REX
There will be a follow up session on Sunday morning.
QSO Today Virtual Ham Expo is the first and only on-line amateur radio convention, since August 2020.? ?
Event tickets and registration cost $15.00 per person for the Expo weekend and 30 day on demand period
March 25-26, 2023
Original message from Rex:
73 Daniel KK4MRN
|
Chuck,
It may have tweeked back. A previous power reading was .56 watts which matches.
That calls into question the accuracy of the watt meter at low values. Have to set up some standard tests maybe to check that out. and do some comparisons with my other watt meters (they generally agree pretty much, at those low levels I suspect the wattmeters internals affect the signal and reading slightly differently)
? ? Thanks,
---John AC9UV
On 02/17/2023 5:55 AM Chuck Carpenter <w5usj@...> wrote:
John,
Your scope indicates an Vrms value of 5.14V.? If you trust the accuracy of the scope, the power would be 528mW.
When dialed up it showed .74w into a 50 ohm dummy.
--
Chuck, W5USJ
|
Re: Ordered my March 2023 Buildathon's updated Sea Sprite+ kit with coupler, key, and Zepp - I have comments and questions
Daniel,
I built the Sea Sprite a few weeks ago. Nice build, clean harmonics. Power about .54w as measured on one of my wattmeters.
I have register for the buildathon and ordered the kit.
I will have to see if I am confident with my code recognition to get on the air then.
I have not built the Lil Squall transiever but have built a couple of pixies and several Rockmite ][ and the topper. I have a 20m Rockmite kit waiting in a box for some time.
I modified one pixie to replace the crystal with a vfo that I put together from a nano ,a DDS chip, a display, and a rotary encoder. Worked nicely. I use the vfo as a frequency standard for my projects.
The pixie kits I have built have marginally acceptable harmonics. They need a LPF added to clean that up I think.?
Buildathons can be hectic. Depends on how fast you go. Rex moves right along and my problem sometimes I get a little behind, or my wife interrupts me... Doing it ahead of time can be done but the buildathon experience is different. In any case with Rex you always learn something new and useful about tools, tool use, or build techniques. In some cases how to fix problems you just caused. A great time is had by all.
? ?Enjoy,
---John AC9UV
On 02/17/2023 5:26 AM Daniel KK4MRN via groups.io <sqldan2000@...> wrote:
Hello,
By the way, I ordered the March 2023 Buildathon's Sea Sprite+ kit.? ?I still need to register for the event though.
I have some comments and questions on down.
lt
Has anybody else ordered this kit?
Anybody else participating in the Buildathon?
Anybody else getting on 7110 the weekend of March 25th and 26th?
Anybody build a QRPme Sea Sprite transceiver or QRPme Lil Squall Transceiver in the past or building one now?
Or even a Pixie transceiver?
The March 2023 Buildathon is a virtual online event.
But, if you're in Los Angeles, California, you can go in person - I think.
March 2023 Buildathon's Sea Sprite+ kit
Includes built-in antenna coupler.?
Additional items are a key and enough wire to construct a 1/2 wave End Fed Zepp antenna.
Good for a new Technician ham to build and Get On The Air.? All they need is a battery and a pair of headphones.
According to the web page, the kit's boards are on order.? So, it will take awhile for Rex to get them, then he has to put on his superman cape and turn out a bunch of kits and mail them in advance of March 25th...? I look forward to building the Sea Sprite+ and getting on the air.? ?I do suggest that anyone participating QRS (slow code) for newbies.? And hopefully I can make a few contacts - well, I hope at least one confirmed contact - with this radio especially the weekend of the Buildathon.? But more contacts the merrier.? ?Let's just make it a week long - weekend to weekend - so others who did not make a contact can keep trying.? Sometimes conditions improve.? ?So, I will be listening.? I will keep the radio on.... And if nobody pounces, I will pounce.
Would it be bad to go ahead and build SST+ kit and try it on the air before March 25th if I get it before the 25th?? Thoughts?
Map of Sea Sprite+ Builders signed up for 3/25 Buildathon
SST+ Version 6 Board layout
SST+ Version 6 Schematic
Presentation at the Buildathon on Saturday March 25th, at 10:00 PDT (1800 UTC)
2-hour session
Build a Simple Station and GOTA (Get On The Air!)
Speaker: Rex Harper W1REX
There will be a follow up session on Sunday morning.
QSO Today Virtual Ham Expo is the first and only on-line amateur radio convention, since August 2020.? ?
Event tickets and registration cost $15.00 per person for the Expo weekend and 30 day on demand period
March 25-26, 2023
Original message from Rex:
73 Daniel KK4MRN
|
John,
?
Your scope indicates an Vrms value of 5.14V.? If you trust the accuracy of the scope, the power would be 528mW.
When dialed up it showed .74w into a 50 ohm dummy.
-- Chuck, W5USJ
|
Ordered my March 2023 Buildathon's updated Sea Sprite+ kit with coupler, key, and Zepp - I have comments and questions
Hello, By the way, I ordered the March 2023 Buildathon's Sea Sprite+ kit.? ?I still need to register for the event though. I have some comments and questions on down. Has anybody else ordered this kit? Anybody else participating in the Buildathon? Anybody else getting on 7110 the weekend of March 25th and 26th? Anybody build a QRPme Sea Sprite transceiver or QRPme Lil Squall Transceiver in the past or building one now? Or even a Pixie transceiver? The March 2023 Buildathon is a virtual online event. But, if you're in Los Angeles, California, you can go in person - I think. March 2023 Buildathon's Sea Sprite+ kitIncludes built-in antenna coupler.? Additional items are a key and enough wire to construct a 1/2 wave End Fed Zepp antenna. Good for a new Technician ham to build and Get On The Air.? All they need is a battery and a pair of headphones. According to the web page, the kit's boards are on order.? So, it will take awhile for Rex to get them, then he has to put on his superman cape and turn out a bunch of kits and mail them in advance of March 25th...? I look forward to building the Sea Sprite+ and getting on the air.? ?I do suggest that anyone participating QRS (slow code) for newbies.? And hopefully I can make a few contacts - well, I hope at least one confirmed contact - with this radio especially the weekend of the Buildathon.? But more contacts the merrier.? ?Let's just make it a week long - weekend to weekend - so others who did not make a contact can keep trying.? Sometimes conditions improve.? ?So, I will be listening.? I will keep the radio on.... And if nobody pounces, I will pounce. Would it be bad to go ahead and build SST+ kit and try it on the air before March 25th if I get it before the 25th?? Thoughts? Map of Sea Sprite+ Builders signed up for 3/25 Buildathon SST+ Version 6 Board layout SST+ Version 6 Schematic
Presentation at the Buildathon on Saturday March 25th, at 10:00 PDT (1800 UTC)
2-hour session
Build a Simple Station and GOTA (Get On The Air!)
Speaker: Rex Harper W1REX
There will be a follow up session on Sunday morning.
QSO Today Virtual Ham Expo is the first and only on-line amateur radio convention, since August 2020.? ?
Event tickets and registration cost $15.00 per person for the Expo weekend and 30 day on demand period
March 25-26, 2023
Original message from Rex:
73 Daniel KK4MRN
|
John,
Very nice.? Thanks for showing us the screen shots.? It is an inspiration for others.?
I like the nice sine wave.? My TTT has 2 peaks. Another ham suggested I use the pot to turn down my power down.? But at least I get output on my scope now.
0.74W ?? ?That is more than I expected from the TTT.?
]
My final was not a can.? It was a plastic PN2222.? Not sure if A or not.? ?But then I lost it.? I replaced it with a part from Mouser.? However, I could see easily where Rex had marked where E B C was on the final.
I will be working on my TTT EZB this weekend to figure out what is wrong with it. I will be going through part by part based on the documentation to make sure it is soldered correctly.? Take some photographs of top and bottom.? Take some measurements.? And then respond to those hams who helped.
I will also build a peak detector with 50ohm dummy load for QRP this weekend.? And build my QRPme Directional Wattmeter kit that I got in the mail the other day.? So, hopefully this can help me get a closer idea of what my power level is from the TTT.??
73 Daniel KK4MRN
|
Group,
I played around with my TT EZ-build and replaced the final with a 2n2222a in a T0-18 case with a heat sink. I think I had the original transistor in wrong so got a much smaller output. (conjecture). because the printed circuit board had the round symbol and the flat side should be facing toward the Base. The socket I put on the board covered most of the writing so I just assumed the flat side orientation would be the same as the other drawings for the non-round transistors. Lesson learned.
When dialed up it showed .74w into a 50 ohm dummy.
? ?Enjoy,
---John AC9UV
|
$11.? That is a good deal.
I have a Radio Shack desoldering iron I got years ago.? I used it last Saturday to desolder pins I put in the wrong place.? And get rid of excess solder that dropped from the iron into a solder hole.? Solder in the solder hole (not sure of correct terminology here) prevented me from inserting a component lead to solder.
I got my desoldering iron at a brick and mortar Radio Shack when they were still around.? Need hook up wire or a LM386, no problem, stop by after work one day and get it.
Radio Shack desoldering iron
Yep, a soldering iron pencil, desolder bulb or pump or a hot air station did not work for me last week.? ?But the desoldering iron did.? Great tool!
73 Daniel KK4MRN
|
Gangue,
I forgot to mention that on their
de-soldering page, they have replacement tips for that tool.
Pretty cheap. I added some of those to my order. I always like to
stash away any specialty items like iron tips to extend the life
of a tool.
Rex
On 2/14/2023 9:41 PM, John Putnum,
AC9UV wrote:
toggle quoted message
Show quoted text
Rex,
Thanks, order
in.? I have a nice little solder sucker that is from Japan
that works well but the timing of lifting solder and
positioning the tip has always been a source of humor.
? ?---John
AC9UV
Gangue,
I just discovered this tool a couple of
days ago...
It is a de-soldering iron which is a
40watt soldering iron with build in solder sucker.
Brilliant! I just wish I had thought of it! I'd retire and
just play with my QRP stuff all day.... Oh wait! I am
retired and play with my QRP stuff all day. Well, if I did
invent it, I would at least have some money in the
bank....
Anyway, I ordered a few for me and made
sure my order was processed before I alerted you guys. I
haven't got mine yet but the reviews looked real promising
so I bought some!
Rex? W1REX
|
Rex,
Thanks, order in.? I have a nice little solder sucker that is from Japan that works well but the timing of lifting solder and positioning the tip has always been a source of humor.
? ?---John AC9UV
On 02/14/2023 8:21 PM Rex Harper <tunacankits@...> wrote:
Gangue,
I just discovered this tool a couple of days ago...
It is a de-soldering iron which is a 40watt soldering iron with build in solder sucker. Brilliant! I just wish I had thought of it! I'd retire and just play with my QRP stuff all day.... Oh wait! I am retired and play with my QRP stuff all day. Well, if I did invent it, I would at least have some money in the bank....
Anyway, I ordered a few for me and made sure my order was processed before I alerted you guys. I haven't got mine yet but the reviews looked real promising so I bought some!
Rex? W1REX
|
Gangue,
I just discovered this
tool a couple of days ago...
It is a de-soldering
iron which is a 40watt soldering iron with build in solder
sucker. Brilliant! I just wish I had thought of it! I'd retire
and just play with my QRP stuff all day.... Oh wait! I am
retired and play with my QRP stuff all day. Well, if I did
invent it, I would at least have some money in the bank....
Anyway, I ordered a few
for me and made sure my order was processed before I alerted
you guys. I haven't got mine yet but the reviews looked real
promising so I bought some!
Rex? W1REX
|
Re: QSO Today BUILDATHON KIT (#9) SST+ on Mar 25 2023
Presentation at the Buildathon on March 25, 2023:
Build a Simple Station and GOTA (Get On The Air!)
Speaker: Rex Harper W1REX
Level: Beginner
Category: Build-A-Thon, Homebrew and Construction, New License - Now What?
?
?
OK, YOU have your amateur license, so what's next?
In this build-a-thon, we will build a very simple 40 meter transceiver that anyone with the desire and a minimal amount of equipment should be able to complete in a single 2 hour session on Saturday March 25th, at 10:00 PDT (1800 UTC). This is a very simple design that should get you on their air on 40 meter CW. A Morse code key and antenna wire is included in the kit. The builder just needs to supply a battery and some headphones.
Assembly should be completed during the 2 hour session with enough time afterwards to try the complete working station on the air. We will coordinate this operating with the hope that we will all make contacts with a followup session on Sunday morning. Of course band conditions, propagation and lots of other factors will attempt to thwart our little on air event but the prospect of a hundred of the same rigs with the same output to the same antenna all operating on the same 7110 Novice frequency should increase the odds that somebody will be contacting somebody else during the event.
Click on this link to order your Simple Station Kit:?
|
Errors can conspire together
On 2023-02-02 8:04 p.m., Daniel KK4MRN via groups.io wrote: So, on the calculator, enter: 25 ¡À ¡Â 10 = 10x
The 10x really is 10 to the x power but I do not know how to show subscripts or superscripts here. The standard way to indicate exponentiation when all you can do is type in a straight line is this: a^b means a raised to the b power. So you want 10^x. So, is my dB math correct? It's fine. Will this work? Yes. But when you flip several switches on your attenuator do not expect extreme accuracy. If you flip the 20 dB, 10 dB, and 2 dB switches you're going to get something close to 32 dB of attenuation but not as close as you might think. The 2 dB attenuator will be pretty close to 2 dB, and the other two will be pretty close to 20 dB and 10 dB, but if your luck is as bad as mine the errors will all be in the same direction and the total error in dB could be as much as 3 times what it is for any one part. Realistically some errors will be on the high side and some on the low side so it probably won't be that bad, but it might be. What you can have reasonable confidence in is that when you've already called for 20 dB and 10 dB attenuation and then flip the 2 dB switch, you're going to have pretty close to 2 dB more attenuation than you had before you flipped it. But the total attenuation might be further from 32 dB than you might think. However it's not going to blow up your tinySA; the error won't be that bad. David VE7EZM and AF7BZ
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Re: My Two Tinned Tunas EZBuild - Transmit Issue
Daniel,
OK lets take your
problems 1x1......
I can hear the
TTT on my receiver on 7.110 when I key down, but that is probably
the crystal oscillator.? I got 2 crystals: 7.030 and 7.110.
Congrats, you have confirmed that your
oscillator circuit is oscillating. You can usually 'hear' the
oscillator oscillation on any and every nearby receiver tuned
into the crystal frequency.
I took out the
final, nothing changed.
Congrats again... looks like you have narrowed
your problem down to the final or output filter...
I hooked it up to an an oscilloscope, nothing.?
OK. Nothing where? Did you check the output of
the oscillator circuit? You should be able to see a small rf
signal on the output (collector) of Q1....and you should check
that it makes it past capacitor C2 (220pf). If it doesn't make it
to the final side of C4 then the final transistor Q2 will have no
signal to amplify.
Well, I wanted to use my TTT EZB for an education - well, looks
like I will be getting one figuring out what is going wrong and
trying to fix it.? LOL
This is one of the benefits of building a
project and NOT having it work! You now get extra FUN diving
into the guts...and learning how your project works.
The LED was
missing or I lost it.? So, I found a red LED.? ?The LED never
lights up.? I think I got A and K correct.? K is the flat side.?
Or the LED consumes too much power.?
Use a jumper to bring 12v power down to the
top of the 1K resistor R10. Check it directly. If it still
doesn't light, you need to check the orientation ( A&K ) and
the soldering job.
And one of the coils did not match what was mentioned in the
documentation.? L2 in the docs:
L2 = 10uH = brown black black (large tubby)
There were 4 coils included in the kit.? I found the other 3.? I
used what was left for L2.
NO.... That's not a good idea. You really
need to use the right parts. What exactly was left over?
Or it's my bad
soldering skills.?
How about a close up pic of the back side for
possible debugging....
Rex? W1REX
|
Re: My Two Tinned Tunas EZBuild - Transmit Issue
Daniel--
Are you using a x10 probe?? Also, I'd try adjusting the power pot down and see if it cleans up.??
-HRS
H. Russell Smith, N0QLT???
?????????????????????????????
On Sunday, February 12, 2023 at 06:24:50 PM CST, Daniel KK4MRN via groups.io <sqldan2000@...> wrote:
Hello Russel,
Not sure why this topic morphed into something else.? I am still trying to fix my radio. There is improvement.
I am getting a signal on my oscilloscope now while the rf output goes into a 50ohm dummy load.? Not sure if the signal looks ok considering what I see at the top.? Two peaks.
If I remove the final, so signal on the scope.
And I can still hear it on a receiver on 7.110 MHz.
Nice to see the red light glowing when I key.
I still need to build my peak detector, but the weekend is almost over...??
73 Daniel KK4MRN
|
QSO Today BUILDATHON KIT (#9) SST+ on Mar 25 2023
Hello all, Rex updated the QRPme web site the other day to include to the following link: QSO Today BUILDATHON KIT (#9) SST+ on Mar 25 2023 $45
QSO Today Virtual Ham Expo?is the first and only on-line amateur radio convention, since August 2020.? ?
Event tickets and registration cost $15.00 per person for the Expo weekend and 30 day on demand period
From the QRPme web page: The Sea Sprite Transceiver + is a new re-working of the Sea Sprite currently in the QRPme tuna can line. The original Sea Sprite was reconfigured into a larger sized tuna can, spreading out the parts a little for an even easier building experience.
Scroll down and see the "Additional Included Items" for the buildathon.? ?
Also, see a previous message from Rex where he said this kit would be a good way for a new ham to get on 40 meters.
Features included in the NEW Sea Sprite transceiver+ are:Bigger pcb has more space between components.Bigger padsWider tracesLarger clearances around padsHigher probability of completion without soldering errorsLatest low insertion loss low pass filterReduced parts count for faster building timeAdded antenna coupler for instant hookup to 1/2 wave End Fed Zepp antenna Additional included items for the QSO Today Expo Buildathon are a straight key kit and enough wire to construct a 1/2 wave End Fed Zepp antenna To GOTA (GetOnTheAir) with everyone else, the builder will need to supply a 12V battery and a set of Walkman style headphones. Of course you will have to have a minimal about of construction tools to build the kit. We are encouraging an online operating event on Saturday night and again early Sunday morning. A whole Buildathon*s (well almost whole) worth of transceivers all operating on the same 40m frequency (7110) at the same time and with the same antenna should provide a practical real time test as to the performance of this QRPp rig. A second QSO Expo session is scheduled on Sunday in which we will discuss the results of the event, provide info as to how to improve your HF operations and also hold a Q&A session as time allows. Docs for the ORIGINAL Sea Sprite are shown below. The new Sea Sprite+ boards are on order and new documentation will be posted as soon as they are developed....
Original message from Rex: /g/QRpmeKits/message/328Note, the original Sea Sprite transceiver Kit is found here in case you want to build it instead for $30
|
Re: My Two Tinned Tunas EZBuild - Transmit Issue
Hello Russel,
Not sure why this topic morphed into something else.? I am still trying to fix my radio. There is improvement.
I am getting a signal on my oscilloscope now while the rf output goes into a 50ohm dummy load.? Not sure if the signal looks ok considering what I see at the top.? Two peaks.
If I remove the final, so signal on the scope.
And I can still hear it on a receiver on 7.110 MHz.
Nice to see the red light glowing when I key.
I still need to build my peak detector, but the weekend is almost over...??
73 Daniel KK4MRN
|
Re: My Two Tinned Tunas EZBuild - Transmit Issue
Rex,
Thanks for the info. I ordered a few 2n2222a with T018 cases and some heat sinks for them. When I have a chance I'll try them out.
I have a few alternative analog SWR/Power meters built and will hook up my double needle meters and see if I can get them 'calibrated' against my other power reading sources. I do love the tweekiness of a good analog meter. It feels like your adding some art the the tuning process.? I always put in a transistor socket for the final since I ordered a tube of sockets a couple of years ago. I agree, for us tinkerers its the best idea.
I and another ham are giving a presentation on the (TR)uSDX to our club. I seem to have interested a few of the members to get that box and the QRP fun seems to be spreading in the group. I regularly bring my latest kits (many from you) to meetings. The other club I belong to is having a show and tell this week, I'll have a handful of rigs, test equipment .. there too. Some time this summer if you would like to do a zoom presentation or talk on QRP things let me know.? I love to spread the special pleasure of minimalism and portability.?
? ? ---John AC9UV
??
? ? ?73
?
On 02/12/2023 11:07 AM Rex Harper <tunacankits@...> wrote:
On 2/12/2023 2:42 AM, John Putnum, AC9UV wrote:
Rex,
Interesting. Your TT2-EZ has a 2N3866 final transistor where the current
design of the Two Tinned Tuna -EZ build uses a 2n2222a for the final. Is that a change? would a heat sinked 2n3866 give more output power? would that be an possible modification?
Thanks, 2n222
---John AC9UV
Gangue,
From the very beginning of QRPme kitting, I have included a SIP socket in my kits for not only using as a crystal socket but also as a transistor socket for the final transistor. Easily replacing a final or even better...experimenting with other transistors as finals has been a hallmark of my efforts to enable others to have FUN with their kits. So the EZB does come with a pair of PN2222 transistors for the oscillator and final. It also comes with a SIP socket and very clearly in the builders guide shows how to use it as sockets for both the crystal and final transistor.
I like the 2N3866 as I have plenty due to getting them for a VERY good price from the GQRP Club! I pop them in my builds and some kits primarily because they are TO5 cans and finding heat sinks for TO5 cans is much easier than finding sinks for TO18s (2N2222A) or TO92s (PN2222). Consulting the datasheets:
transistor? pkg?? Max collector current watts dissipation
2N2219A?? TO39??? 600mA/800pk ?? ??? ??? ??? 3W
2N2222A? TO18???? 600mA/800pk ?? ?? ??? ??? 1.8W
PN2222A? TO92??? 600mA? ????? ??? ?? ?? ??? ? ?? 625mW
2N3866??? TO39??? 400mA??? ??? ??? ??? ??? ??? ??? 1W
I'd rather 'push' a whoosier final WITH a heat sink than a marginally better transistor without one... AND trying to find obsolete 2N2219A s and 2N2222s in cans is a challenge along with coming up with the coin to buy them! Jameco Electronics has 2N2222A transistors at $1.29ea which is a little cheaper than they used to be but no heat sinks for them. But their performance in the EZB is not that much better. I yanked the 2N3866 in my EZB that I tested last night and plugged in a PN2222. Power readings were pretty much the same without touching the trimmer pot. I suspect that if you wanted to run higher supply voltages you would start to bump into the collector current and heat dissipation limits and start to melt epoxy.
I really wanted to be in Orlando this weekend for the Hamcation! When my dad was alive and less than a hour away, I would take in the show nearly every year. The low rent building out back was my GOTO source for things like NOS heat sinks etc. Another GOTO place is Skycraft Surplus. Apparently they have moved into a bigger space since I last visited them....and bought every TO5 heat sink in their bin. I had 150+ in my suitcase on the way home. Long since used up but more easily findable than a TO92 or TO18 heat sink. They sell online but not as much FUN as being there in person and getting the full touchie feelie experience. They make the old RS stores look like an end cap in a truck stop convenience store!
Rex? W1REX
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Re: My Two Tinned Tunas EZBuild - Transmit Issue
On 2/12/2023 2:42 AM, John Putnum,
AC9UV wrote:
Rex,
Interesting. Your TT2-EZ has a 2N3866 final transistor where the current
design of the Two Tinned Tuna -EZ build uses a 2n2222a for the final. Is that a change? would a heat sinked 2n3866 give more output power? would that be an possible modification?
Thanks,
---John AC9UV
Gangue,
From the very beginning of QRPme kitting, I have included a SIP
socket in my kits for not only using as a crystal socket but also
as a transistor socket for the final transistor. Easily replacing
a final or even better...experimenting with other transistors as
finals has been a hallmark of my efforts to enable others to have
FUN with their kits. So the EZB does come with a pair of PN2222
transistors for the oscillator and final. It also comes with a SIP
socket and very clearly in the builders guide shows how to use it
as sockets for both the crystal and final transistor.
I like the 2N3866 as I have plenty due to getting them for a VERY
good price from the GQRP Club! I pop them in my builds and some
kits primarily because they are TO5 cans and finding heat sinks
for TO5 cans is much easier than finding sinks for TO18s (2N2222A)
or TO92s (PN2222). Consulting the datasheets:
transistor? pkg?? Max collector current watts dissipation
2N2219A?? TO39??? 600mA/800pk ?? ??? ??? ??? 3W
2N2222A? TO18???? 600mA/800pk ?? ?? ??? ??? 1.8W
PN2222A? TO92??? 600mA? ????? ??? ?? ?? ??? ? ?? 625mW
2N3866??? TO39??? 400mA??? ??? ??? ??? ??? ??? ??? 1W
I'd rather 'push' a whoosier final WITH a heat sink than a
marginally better transistor without one... AND trying to find
obsolete 2N2219A s and 2N2222s in cans is a challenge along with
coming up with the coin to buy them! Jameco Electronics has
2N2222A transistors at $1.29ea which is a little cheaper than they
used to be but no heat sinks for them. But their performance in
the EZB is not that much better. I yanked the 2N3866 in my EZB
that I tested last night and plugged in a PN2222. Power
readings were pretty much the same without touching the trimmer
pot. I suspect that if you wanted to run higher supply voltages
you would start to bump into the collector current and heat
dissipation limits and start to melt epoxy.
I really wanted to be in Orlando this weekend for the Hamcation!
When my dad was alive and less than a hour away, I would take in
the show nearly every year. The low rent building out back was my
GOTO source for things like NOS heat sinks etc. Another GOTO place
is Skycraft Surplus. Apparently they have moved into a bigger
space since I last visited them....and bought every TO5 heat sink
in their bin. I had 150+ in my suitcase on the way home. Long
since used up but more easily findable than a TO92 or TO18 heat
sink. They sell online but not as much FUN as being there in
person and getting the full touchie feelie experience. They make
the old RS stores look like an end cap in a truck stop convenience
store!
Rex? W1REX
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Re: My Two Tinned Tunas EZBuild - Transmit Issue
I hear what Rex is saying and kind of agree. I always say 'in region of' or 'about' / 'around' when I'm quoting measurements as most of my test gear is not factory grade or calibrated.
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I've known my NM0S QRPometer long enough to get a feel for it's accuracy and it's amazingly good.
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It's definitely difficult to measure QRPp transmitters accurately, the power level is so small and the act of measuring can affect the result. My oscilloscope peak voltage readings confirmed the result of my QRPometer - at 12.6v (minus protection diode), I'm getting around 400mW output on 40m. This result also ties up nicely with Rex's result.
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So the ball park figure is 400mW.
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My TTT EZB was fitted with a 2N3866 but I used SIP sockets, so I found a 2N2222A TO-18 and swapped it in - I saw no difference in power output at all. I'm guessing that the TO-5 2N3866 would be a little more robust but I think if you're managing to pop a final at 400mW, something is massively wrong!
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Unless for personal amusement, squeezing every bit of last power out of a circuit is futile. I never understood the guys bragging about their RockMites having 'x' much power because they've changed 'Y' etc. The difference in signal to the guy at the other end would be undetectable. If your QRPp signal is getting there, it doesn't matter if it's 300mW or 500mW, there's no difference. You'd have to increase the power to around 2W to get one S point difference in recieved signal strength.
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To increase power, you'd have to improve the matching in the PA circuit and improve the low pass filter. The TTTEZB schematic shows the details of how to do this. My TTT EZB modified as suggested on schematic gives me around 850mW (uncalibrated but trusted meter, YMMV!).
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73, Colin
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