Hi all
?
I have just completed my first 20 amp build.?
This is my first foray into surface mount soldering and I think all has gone well.
Really cool stuff.
?
I am building this amp to accompany a Hermes Lite to turn it into a full 15w blowtorch.
The Hermes has an "RF Out" that bypasses the internal 5 Watt PA.
?
I have measured that output on all bands.
It ranges from 72mws on 10 meters
Down to 42mw on 40 meters.
?
My hunch is to calculate the Pi Attenuator for 41 mw.? Is that a good bet?
?
Here are my numbers - check me out and let me know what will be best.??
I failed Algebra 2 in High School.
?
To attenuate 42 mw to 1mw, I need to attenuate 41mw or 16.12 db
?
The values I come up with are
68.5276
156.026
68.5276
?
So real values
68
160
68
?
Does this look right to you guys ?
What would you all suggest?
?
Thanks again for this great group.
Looking forward to building the T41 !
?
72 David
W0NP
?
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Agree. I have a bottle of liquid flux sitting on the table and use it mostly when I solder ICs onto the board. I rarely use the paste anymore.
Jack, W8TEE
On Monday, May 19, 2025 at 02:25:22 PM EDT, jerry-KF6VB <jerry@...> wrote:
On 2025-05-19 09:41, somebody wrote: holes. However for the PE4312 and other smaller chips, the paste
placed was either bridging all the pins or non-existent.
*** I've had good luck thinning the solder paste with liquid flux. Makes it more liquidy and less lumpy. Makes it much easier to dab on a smidge with a needle or the tip of a brand new Xacto knife. - Jerry, KF6VB
-- Jack, W8TEE
|
Re: Back in the Saddle - soldering video
Yep...this is the video:
Jack, W8TEE
On Monday, May 19, 2025 at 02:31:21 PM EDT, Lee Johnson <lee47@...> wrote:
On Sunday, May 18, 2025 at 07:25:46 PM CDT, Jack, W8TEE via groups.io <jjpurdum@...> wrote:
This is a good video and should convince others that soldering SMD parts to a PCB isn't that tough. Keep in mind, this is a difficult part to solder to a board. By comparison, a 1206 SMD resistor or cap is child's play. This technique can also be used on the Si5351 which is probably one of the hardest parts to solder in the T41. If my fat fingers and poor eyes can do it, anyone can.
Jack, W8TEE
On Sunday, May 18, 2025 at 07:05:43 PM EDT, Phil Taylor via groups.io <philbyt1@...> wrote:
John
?
This may help. This guy uses an alternate method. Microscope is an absolute necessary item. One extra thing I do is add some flux paste to the chip edge before running the soldering iron along the pins to neaten and remove any bridges.
?
?
?
Regards?
Phil
VK2KKZ
--
Jack, W8TEE
-- Jack, W8TEE
|
Re: Back in the Saddle - soldering video
On Sunday, May 18, 2025 at 07:25:46 PM CDT, Jack, W8TEE via groups.io <jjpurdum@...> wrote:
This is a good video and should convince others that soldering SMD parts to a PCB isn't that tough. Keep in mind, this is a difficult part to solder to a board. By comparison, a 1206 SMD resistor or cap is child's play. This technique can also be used on the Si5351 which is probably one of the hardest parts to solder in the T41. If my fat fingers and poor eyes can do it, anyone can.
Jack, W8TEE
On Sunday, May 18, 2025 at 07:05:43 PM EDT, Phil Taylor via groups.io <philbyt1@...> wrote:
John
?
This may help. This guy uses an alternate method. Microscope is an absolute necessary item. One extra thing I do is add some flux paste to the chip edge before running the soldering iron along the pins to neaten and remove any bridges.
?
?
?
Regards?
Phil
VK2KKZ
--
Jack, W8TEE
|
On 2025-05-19 09:41, somebody wrote: holes. However for the PE4312 and other smaller chips, the paste
placed was either bridging all the pins or non-existent.
*** I've had good luck thinning the solder paste with liquid flux. Makes it more liquidy and less lumpy. Makes it much easier to dab on a smidge with a needle or the tip of a brand new Xacto knife. - Jerry, KF6VB
|
I don't have the video but I can describe my method. I use a toothpick or pin and spread a very light coat of paste flux over all the lands to be soldered. Then I place?the part using a magnifier and tack one or two pins in opposite corners, checking and correcting alignment until it is perfect.? Then I apply more paste flux across the pin/pad junctions all the way around. With a chisel tip I apply heat to the end of the pin and tab, along with a very small touch of solder. The flux draws the solder into place nicely.? Go all around the chip soldering each side, then check for bridges and dry joints. Bridges are dealt with by the end of a piece of solder wick dipped in flux, slide up the pad/ pin junction and apply heat. I follow up with the chisel end (dry) touching 2-3 pins at once and watch how the pins take solder.?
Bridges further up the pins can be challenging- a small diameter copper strand coated with flux is passed behind the pins and body of the chip. When it hits the bridge it will probably stop, heat that area until it passes. More flux, get ?the pins and that wire hot, and withdraw.?
Eden DSP Ron Taylor has presented this technique along with others. I am successfully soldering TSSOP PicDSP quad packages with 68 pins all round.? I use a rosin active flux in both liquid and paste form. A stand of 18 ga wire seems about right (26-30 ga strand)
Larry KB3CUF
There was a post yesterday that presented a YouTube video URL which showed how to solder small IC (e.g., like the Si5351 and 1808) on a PCB. It was a very good video and also showed the easy way to fix "pin bridges". I must have erased it, cuz I can't find the video, but maybe someone else can report it.
Jack, W8TEE
?
Thanks. My biggest problem is the two PE4312 chips (U3-U12). My first attempt using T5 Chipquik solder paste and a heat gun didn't go well. I couldn't get the solder to flow...though that is hard to see as all the 20 pins are under the chip.
For the main board I used a reflow oven, which worked perfectly. However, with the larger SMD components, like the TR1, I was afraid that before I got all the components placed and the board moved to the oven, some would shift position. So, I've hand soldered
all of the U chips. I will now attempt the rest of the chips and components using the reflow oven. For the gigantic ;-) 1206 components, I used a toothpick to place solder paste on the pads, with the PE4312, I guess I will need to use a needle.?
I have tried to brace my shaky hand when placing these microscopic parts, but with pins only 0.23mm even the slightest movement will smear the paste across all the pins.
I was able to 3D print the solder paste stencil, but it became a mess with all the non-SMD component holes being filled with paste. If I try that again, I will edit the stencil to remove those holes. However for the PE4312 and other smaller chips, the
paste placed was either bridging all the pins or non-existent.?
--
Jack, W8TEE
|
There was a post yesterday that presented a YouTube video URL which showed how to solder small IC (e.g., like the Si5351 and 1808) on a PCB. It was a very good video and also showed the easy way to fix "pin bridges". I must have erased it, cuz I can't find the video, but maybe someone else can report it.
Jack, W8TEE
?
Thanks. My biggest problem is the two PE4312 chips (U3-U12). My first attempt using T5 Chipquik solder paste and a heat gun didn't go well. I couldn't get the solder to flow...though that is hard to see as all the 20 pins are under the chip.
For the main board I used a reflow oven, which worked perfectly. However, with the larger SMD components, like the TR1, I was afraid that before I got all the components placed and the board moved to the oven, some would shift position. So, I've hand soldered
all of the U chips. I will now attempt the rest of the chips and components using the reflow oven. For the gigantic ;-) 1206 components, I used a toothpick to place solder paste on the pads, with the PE4312, I guess I will need to use a needle.?
I have tried to brace my shaky hand when placing these microscopic parts, but with pins only 0.23mm even the slightest movement will smear the paste across all the pins.
I was able to 3D print the solder paste stencil, but it became a mess with all the non-SMD component holes being filled with paste. If I try that again, I will edit the stencil to remove those holes. However for the PE4312 and other smaller chips, the
paste placed was either bridging all the pins or non-existent.?
--
Jack, W8TEE
|
And Hamvention is OVER!
We had a great time¡ in-doors this year. ?Sold 50 fill T41 board sets, ten 20W PAs, ten of the latest T41 books (signed/personalized editions), and many other kits. ?Suitcase is a lot lighter. ??
Jack and Al were at my booth (right across from ICOM!) Friday, and Al was there on Saturday. ?After talking to the many many people who stopped by (Thank you!) i received good information on what folks wanted/needed next in terms of kits and upgrades to the T41. ?Loud and clear. ? So partially pre-populated boards, 100W module, Antenna tuner, and multipurpose audio board with usb that passes commands and audio (sound card). ?Got it! ?All good stuff. ?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
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Show quoted text
On May 17, 2025, at 3:17?PM, K9HZ <bill@...> wrote:
? I Just a few boards left at Hamvention. ?When they are gone its back to mail order sales. ?Drop by and get what you need.
Ps i also have 7 signed (by Jack and Al) third editions of the book available at a discount from the Amazon price!!!
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
|
Bill,
Excellent! Should ease some concerns with soldering those small parts.
Al
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Show quoted text
As the tariff stuff eases, i will look into stocking RF boards with the PE4302 and the si5351 pre-populated. ?After talking with Al¡ i agree, it will be a good way to get more people to build the radio and it takes the fear of placing these
parts off the table.?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ
?
Owner - Operator
Big Signal Ranch ¨C K9ZC
Staunton, Illinois
?
Owner ¨C Operator
Villa Grand Piton - J68HZ
Soufriere, St. Lucia W.I.
Rent it: www.VillaGrandPiton.com
email:??bill@...
?
On May 18, 2025, at 8:06?AM, John Owens K1JO via groups.io <johnowenschina@...> wrote:
?
Thanks. My biggest problem is the two PE4312 chips (U3-U12). My first attempt using T5 Chipquik solder paste and a heat gun didn't go well. I couldn't get the solder to flow...though that is hard to see as all the 20 pins are under the chip.
For the main board I used a reflow oven, which worked perfectly. However, with the larger SMD components, like the TR1, I was afraid that before I got all the components placed and the board moved to the oven, some would shift position. So, I've hand soldered
all of the U chips. I will now attempt the rest of the chips and components using the reflow oven. For the gigantic ;-) 1206 components, I used a toothpick to place solder paste on the pads, with the PE4312, I guess I will need to use a needle.?
I have tried to brace my shaky hand when placing these microscopic parts, but with pins only 0.23mm even the slightest movement will smear the paste across all the pins.
I was able to 3D print the solder paste stencil, but it became a mess with all the non-SMD component holes being filled with paste. If I try that again, I will edit the stencil to remove those holes. However for the PE4312 and other smaller chips, the
paste placed was either bridging all the pins or non-existent.?
|
As the tariff stuff eases, i will look into stocking RF boards with the PE4302 and the si5351 pre-populated. ?After talking with Al¡ i agree, it will be a good way to get more people to build the radio and it takes the fear of placing these parts off the table.?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
toggle quoted message
Show quoted text
On May 18, 2025, at 8:06?AM, John Owens K1JO via groups.io <johnowenschina@...> wrote:
? Thanks. My biggest problem is the two PE4312 chips (U3-U12). My first attempt using T5 Chipquik solder paste and a heat gun didn't go well. I couldn't get the solder to flow...though that is hard to see as all the 20 pins are under the chip.
For the main board I used a reflow oven, which worked perfectly. However, with the larger SMD components, like the TR1, I was afraid that before I got all the components placed and the board moved to the oven, some would shift position. So, I've hand soldered all of the U chips. I will now attempt the rest of the chips and components using the reflow oven. For the gigantic ;-) 1206 components, I used a toothpick to place solder paste on the pads, with the PE4312, I guess I will need to use a needle.?
I have tried to brace my shaky hand when placing these microscopic parts, but with pins only 0.23mm even the slightest movement will smear the paste across all the pins.
I was able to 3D print the solder paste stencil, but it became a mess with all the non-SMD component holes being filled with paste. If I try that again, I will edit the stencil to remove those holes. However for the PE4312 and other smaller chips, the paste placed was either bridging all the pins or non-existent.?
|
Re: [SoftwareControlledHamRadio] Just a few
Hey everyone! ?Tim, W4YN donated some very nice 3 wire pre-made cables, twisted, to be used to connect the teensy audio hat to the main board (the 90 degree pins). ?I will include these free of charge¡ one with each main board. ?
Thanks Tim!
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
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On May 18, 2025, at 8:12?AM, Tim O'Rourke via groups.io <w4yn@...> wrote:
?I am aiming for? 11:30 to stop by Sent using myEarthLink On Sat May 17 18:51:31 EDT 2025 K9HZ wrote:
My spot is #2607¡ its just across from ICOM in building 2.
?
I was out at your spot earlier but you were not there¡
?
?
Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ
?
Owner - Operator
Big Signal Ranch ¨C K9ZC
Staunton, Illinois
?
Owner ¨C Operator
Villa Grand Piton ¨C J68HZ
Soufriere, St. Lucia W.I.
Rent it:
?
Moderator: North American QRO Group at Groups.IO.
Moderator: Amateur Radio Builders Group at Groups.IO.
?
email:?
bill@...
?
?
?
Send you spot again short memory among other things Hi. I am at Roosters for dinner.
Tim
Sent using myEarthLink
On Sat May 17 16:49:18 EDT 2025 K9HZ wrote:
Yes. ?Will be there on Sunday til noon!!!
?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ
?
Owner - Operator
Big Signal Ranch ¨C K9ZC
Staunton, Illinois
?
Owner ¨C Operator
Villa Grand Piton - J68HZ
Soufriere, St. Lucia W.I.
Rent it:
?
email:??
bill@...
?
?Will you be here Sunday?
Tim
Sent using myEarthLink
On Sat May 17 16:16:56 EDT 2025 K9HZ wrote:
I Just a few boards left at Hamvention. ?When they are gone its back to mail order sales. ?Drop by and get what you need.
Ps i also have 7 signed (by Jack and Al) third editions of the book available at a discount from the Amazon price!!!
?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ
?
Owner - Operator
Big Signal Ranch ¨C K9ZC
Staunton, Illinois
?
Owner ¨C Operator
Villa Grand Piton - J68HZ
Soufriere, St. Lucia W.I.
Rent it:
?
email:??
bill@...
?
|
Thanks Phil.?
Wow, he applied way more than I would have thought possible. I'd be afraid that using that much would create solder bridges under the chip. I'll dilute the paste like he says but try to add it a bit more sparingly. Then I'll place it with all of the other components in the reflow oven.
Fingers crossed.
|
This is a good video and should convince others that soldering SMD parts to a PCB isn't that tough. Keep in mind, this is a difficult part to solder to a board. By comparison, a 1206 SMD resistor or cap is child's play. This technique can also be used on the Si5351 which is probably one of the hardest parts to solder in the T41. If my fat fingers and poor eyes can do it, anyone can.
Jack, W8TEE
On Sunday, May 18, 2025 at 07:05:43 PM EDT, Phil Taylor via groups.io <philbyt1@...> wrote:
John
?
This may help. This guy uses an alternate method. Microscope is an absolute necessary item. One extra thing I do is add some flux paste to the chip edge before running the soldering iron along the pins to neaten and remove any bridges.
?
?
?
Regards?
Phil
VK2KKZ
-- Jack, W8TEE
|
John
?
This may help. This guy uses an alternate method. Microscope is an absolute necessary item. One extra thing I do is add some flux paste to the chip edge before running the soldering iron along the pins to neaten and remove any bridges.
?
?
?
Regards?
Phil
VK2KKZ
|
Thanks. My biggest problem is the two PE4312 chips (U3-U12). My first attempt using T5 Chipquik solder paste and a heat gun didn't go well. I couldn't get the solder to flow...though that is hard to see as all the 20 pins are under the chip.
For the main board I used a reflow oven, which worked perfectly. However, with the larger SMD components, like the TR1, I was afraid that before I got all the components placed and the board moved to the oven, some would shift position. So, I've hand soldered all of the U chips. I will now attempt the rest of the chips and components using the reflow oven. For the gigantic ;-) 1206 components, I used a toothpick to place solder paste on the pads, with the PE4312, I guess I will need to use a needle.?
I have tried to brace my shaky hand when placing these microscopic parts, but with pins only 0.23mm even the slightest movement will smear the paste across all the pins.
I was able to 3D print the solder paste stencil, but it became a mess with all the non-SMD component holes being filled with paste. If I try that again, I will edit the stencil to remove those holes. However for the PE4312 and other smaller chips, the paste placed was either bridging all the pins or non-existent.?
|
They are real, not just vaper writers ?
I met Bill and Al today at the hamfest.? I bought more parts, bought a book, and took pictures of a real, working? T-41 !!
Thanks so much.
KD4TNX?
|
I Just a few boards left at Hamvention. ?When they are gone its back to mail order sales. ?Drop by and get what you need.
Ps i also have 7 signed (by Jack and Al) third editions of the book available at a discount from the Amazon price!!!
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
|
It is here:
On Saturday, May 17th, 2025 at 6:24 AM, John Owens K1JO via groups.io <johnowenschina@...> wrote:
Is there an RF board assembly document? I searched first :)
|
Is there an RF board assembly document? I searched first :)
|
I am currently at Hamvention with a plethora of boards and kits. ?All set up in booth #2607 just across the floor from ICOM. ?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois ? Owner ¨C Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
email:??bill@... ?
|
Jack, W8TEE
K9HZ
John Owens K1JO
Jerry