JUMA PA100D Build Log

General discussion

JUMA PA100D Build Log

Postby VK4GRM » 05 Aug 2018 10:37

Hi

I spent some time documenting my build of the JUMA PA100D power amplifier and will upload it to the forum so that others can use it for guidance when building their own. There will be multiple documents as I have used a lot of graphics and they tend to blow out the size of a single document. The documents contain a combination of images that are on the Juma web site and photos that I have taken as my build progressed.

Ed WA4MZS has kindly provided some review comments and provided some additional information in some of the documents.

Happy to take any comments to make these better for others building the PA100D.

Unfortunately I have found that there is a 2MB limit on the file sizes allowed to be uploaded so some of the graphics have been degraded when I compressed the files. If anyone wants a uncompressed version please let me know and I will send it direct.

Kind Regards

Greg

VK4GRM
Attachments
Building the JUMA 100W PA - Main BoardVC.pdf
Main Board Build Notes
(1.25 MiB) Downloaded 130 times
Building the JUMA 100W PA - RF AmplifierV3C.pdf
RF Amplifier Board Build Notes
(1.97 MiB) Downloaded 128 times
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia

Re: JUMA PA100D Build Log

Postby VK4GRM » 14 Aug 2018 11:15

Hi Attached are the next two additions to the PA100D build log.

Kind Regards

Greg

VK4GRM
Attachments
Building the JUMA 100W PA - Frequency Sense Module.pdf
Frequency Sense Module Build Log
(976.38 KiB) Downloaded 121 times
Building the JUMA 100W PA - Digital Board.pdf
Digital Board Build Log
(1.37 MiB) Downloaded 98 times
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia

Re: JUMA PA100D Build Log

Postby GM0EUL » 20 Sep 2018 14:43

This is excellent, really useful. I ordered a JUMA PA100-D yesterday and it shipped today. I've been looking through the pictures and tips on the website and these notes will really help.

73
Peter
GM0EUL
CwOps 1899
SKCC 16307
GM0EUL
 
Posts: 5
Joined: 19 Sep 2018 17:08
Location: UK

Re: JUMA PA100D Build Log

Postby VK4GRM » 27 Sep 2018 11:11

Hi Peter

I am glad you found it useful. If you run into any problems let me know as I may be able to help.
If you need higher resolution pictures of any thing I have probably got them here somewhere.
I found it very useful to have someone to bounce ideas off even if they were on the other side of the world.
Ed WA4MZS was a great help to me when I was building and getting mine to work.

I plan to upgrade the software on my amp at some stage and also to calibrate it properly but this will be a little while as we are getting some house renovations done at the moment.

I was planning to do a article on test and calibration to finish the series. Not sure when that will be at the moment.

73s

Greg
VK4GRM
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia

Re: JUMA PA100D Build Log

Postby GM0EUL » 27 Sep 2018 22:36

Hi Greg
Thanks. I was wondering what to do if I couldn't get it to work. I've built the amplifier module which took me about day and I've made a start on the main board, so far the resistors are on. Hopefully I'll get the time to finish it over the weekend. I've built plenty of small things but mainly with through-hole components on homemade pcbs. This is the first major thing with extensive use of smd components. So far so good. I'm getting faster and its not as difficult as I expected. I don't know how I'll do with the microcontroller but I've watched some videos and it should be ok.

Did yours work from the start or is there much troubleshooting and fettling before it works?

Here is a picture of my amplifier board
IMG_20180925_231104.jpg
amplifier board pa100-d


I'm planning to use it with a newly acquired K2

73, Peter GM0EUL
GM0EUL
CwOps 1899
SKCC 16307
GM0EUL
 
Posts: 5
Joined: 19 Sep 2018 17:08
Location: UK

Re: JUMA PA100D Build Log

Postby VK4GRM » 03 Oct 2018 10:19

Hi Peter

I know what it feels like to do a project with so many surface mount components when you have only ever done through hole components. As you say you get faster as you go along.
the main thing is to sort all of the components out first and to install all of them in the order identified. The JUMA guys have picked what appears to be the best order for installation and I recommend following it.

Your picture of the PA stage looks good. My only comment would be to possibly apply a little more head to the transistor terminals. The solder on the top does not appear to have wetted properly and this may indicated that it has not wetted properly to the PCB below. This is were nearly all of the RF is generated so you need low impedance joints here.

Other than that I suggest you follow my Testing instructions on the PA Document on this website to make sure that you don't have any shorts to ground. Check that there is clearance between the component leads above the rear panel.

I had a few problems mainly caused by shorts in the ribbon cables that I made up. I would suggest that you bell out the adjacent wires in the ribbon cables to make sure that you haven't got any shorts. That was my main failing. Also when you do the PIC make absolutely sure that you don't have any shorted pins. I did have between 5V and ground and it took me a few weekends to eventually find it. There are a few of these on adjacent pins on the PIC and they can be very hard to spot if they are behind the pins as was my case. On the 5V rail there are a lot of components to lift if you need to go looking for the problem.

Even though this is a very complex bit of kit it does go together with minimal problems if you take care as you go along.

Keep up the good work

73s

Greg
VK4GRM
Attachments
IMG_7741_50_50.jpg
VK4GRM PA board
pa100-amp-module[1].jpg
PA image from JUMA website
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia

Re: JUMA PA100D Build Log

Postby GM0EUL » 07 Oct 2018 13:08

Hi Greg
Just finished building my PA100-D. I haven't properly tested it yet but so far it appears to be working. I've powered it up from a current limited 1.5A 12V switching PSU from an old WiFi router. Everything lights up and operates as it should! Surprised and delighted. Next to put a tiny bit of RF into it and see if it switches and amplifies as it should. Then wind it up properly and try a qso. One of the filter torroids arrived broken and one of the front panel spacers was the wrong size otherwise everything was absolutely excellent and I'm a complete convert to surface mount.

Your write-up helped me avoid all sorts of pitfalls that I would otherwise have probably fallen into. Mainly drawing my attention to the orientation of some components and the possibility of bridges behind the pins on the microcontroller. I spent a long time re-flowing and wicking the solder until I was happy with it. I found that by sitting back and shining a light on it I could see reflections where I expected darkness and could go back and sort them out.

I'll let you know how the next stage goes.

73
Peter
GM0EUL
GM0EUL
CwOps 1899
SKCC 16307
GM0EUL
 
Posts: 5
Joined: 19 Sep 2018 17:08
Location: UK

Re: JUMA PA100D Build Log

Postby VK4GRM » 15 Oct 2018 08:22

Hi Peter

I am glad you have got it working. I have been very happy with mine and once I get a bit of spare time I will update the software with Adrian's (5B4AIY) latest version of the code.

The solder bridges behind the pins on the PIC are a real headache to find. I took me a couple of weekends to find mine.

I have a problem with my main PSU at the moment that needs fixing. Cooling fan is not coming on soon enough. There is always something that is a problem


73s

Greg
VK4GRM
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia

Re: JUMA PA100D Build Log

Postby GM0EUL » 15 Oct 2018 13:00

Hi Greg

Its all fully working now and I've used it in a couple of CwOps and SKCC events with my K2 and the combination is fantastic. I've been sent a replacement torroid and spacer but not sure whether its necessary to fit them or keep them just in case. I cut down the one overlong spacer supplied and its fine, and I super-glued the broken torroid and it seems to be performing to spec. I'm reluctant to fiddle as its working so well. I'll read up about the latest firmware, I hadn't really considered it and don't know very much about the benefits.

Overall I'm delighted. A beautiful kit and it pretty much worked first time. Thanks for your help and the very informative documentation.

73
Peter, GM0EUL
GM0EUL
CwOps 1899
SKCC 16307
GM0EUL
 
Posts: 5
Joined: 19 Sep 2018 17:08
Location: UK

Re: JUMA PA100D Build Log

Postby VK4GRM » 02 Dec 2018 10:02

Hi Peter

I have just successfully updated the software on my PA100D.
If you intend to try I suggest you have a read of my posts on Adrian's part of the Forum.
Adrian has been a great help in getting this sorted for me as a ran into a few problems.

I have included some details to help with getting it done.

73s Greg VK4GRM
VK4GRM
 
Posts: 22
Joined: 18 Jun 2018 20:00
Location: Australia


Return to Juma Discussion

Who is online

Users browsing this forum: No registered users and 1 guest

cron