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JUMA TX-500 first power up. No display

I finally finished the power supply wiring for my TX-500 today. Unfortunately first power up didn't go very well. Current limited supply set to 14V 1.5A Press the green power button. No display. If I hold the button in the current comes up to 1.25A then drops to 750mA. When I release the button the ...
by NE5U
13 Jun 2018 21:59
 
Forum: Juma Discussion
Topic: JUMA TX-500 first power up. No display
Replies: 0
Views: 6171

Re: TX 500 Filter orientation

Per the documentation I can answer my questions. Ignore the dot on the filter or silkscreen. The dot on the filter goes to the left Yes... I installed my current sense transformers correctly. That's what I get for dragging this build out for months. Couldn't help it. I work to pay the bills and buy ...
by NE5U
21 Nov 2017 23:26
 
Forum: Juma Discussion
Topic: TX 500 Filter orientation
Replies: 2
Views: 4461

Re: IRFI540N install orientation and lack of availability

I found all of the documents so I can answer the orientation question. As you would expect, the MOSFET is attached to the back panel.
by NE5U
21 Nov 2017 23:23
 
Forum: Juma Discussion
Topic: IRFI540N install orientation and lack of availability
Replies: 1
Views: 3841

IRFI540N install orientation and lack of availability

Q6 and Q7 are somewhat unobtanium. I found some allegedly NOS for sale on eBay but that's always a crap shoot. That said, the crooked logo on the supplied transistors makes them suspect as well. The scarcity of these parts does not bode well for future repairs. Is there a substitute? The silkscreen ...
by NE5U
21 Nov 2017 22:50
 
Forum: Juma Discussion
Topic: IRFI540N install orientation and lack of availability
Replies: 1
Views: 3841

Re: TX500 Control board hardware?

Not much activity on this forum :/
by NE5U
21 Nov 2017 21:32
 
Forum: Juma Discussion
Topic: TX500 Control board hardware?
Replies: 1
Views: 3770

Re: FS: TRX-1, TX-1 & RX-1 Kits unbuilt complete

I am sure you have sold these by now but stranger things have happened. Do you still have the kits and if so what would be your lowest asking price? I am attempting to teach my son kit building and I think it is time for him to try it on his own radio. WJ5G Callen QRZ says "Callsign Surrendere...
by NE5U
21 Nov 2017 21:31
 
Forum: Juma Discussion
Topic: FS: TRX-1, TX-1 & RX-1 Kits unbuilt complete
Replies: 2
Views: 5865

TX 500 Filter orientation

I'm a little confused by the dot on the silkscreen and the dot on T1/T2. They don't match and there's no orientation where they do match (that I can see). I haven't installed anything. I just put the part on the board for reference. The filter has a dot on the left pad and the silkscreen has the dot...
by NE5U
21 Nov 2017 21:23
 
Forum: Juma Discussion
Topic: TX 500 Filter orientation
Replies: 2
Views: 4461

Re: JUMA CMCD Xmitter Main Board components?

The second pic showed up. Awesome I literally just picked up the chip and sighted down the edge, sure enough, one of the long sides is chamfered. I couldn't see the chamfer when looking down on it with my 2x visor and I was ready to disagree. :D Normally I would be working with a microscope but I'm ...
by NE5U
07 Nov 2017 13:24
 
Forum: Juma Discussion
Topic: JUMA CMCD Xmitter Main Board components?
Replies: 3
Views: 5385

Re: JUMA CMCD Xmitter Main Board components?

IC10 dos not have a Pin 1 designator so I'm not sure how to orient it. WTH? Why can't I post a link to a second image?

Image
by NE5U
07 Nov 2017 00:51
 
Forum: Juma Discussion
Topic: JUMA CMCD Xmitter Main Board components?
Replies: 3
Views: 5385

JUMA CMCD Xmitter Main Board components?

There are two components on the main board that I'm having trouble with. D8- the parts list that came in the bag says it is a SM6T18A however I don't see that number on the part. I soldered it in place because there was really no other place for it. http://wildlightimagingstudio.com/img/s10/v105/p26...
by NE5U
07 Nov 2017 00:46
 
Forum: Juma Discussion
Topic: JUMA CMCD Xmitter Main Board components?
Replies: 3
Views: 5385
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