Search found 178 matches

Return to advanced search

Juma TRX-2 Current Consumption

In providing some assistance to various constructors over the years, I have often been asked what is the typical current consumption of a correctly adjusted Juma TRX-2. Attached is a PDF giving the current consumption measured using my transceiver under various operating conditions. Hopefully this w...
by 5B4AIY
22 Mar 2017 08:45
 
Forum: Juma Discussion
Topic: Juma TRX-2 Current Consumption
Replies: 0
Views: 749

Re: Problem flashing Firmware

Hi, Mike, Glad to have been of some assistance. I had forgotten that when you wish to flash the firmware, you need to jumper the power switch, thanks for reminding me! The latest firmware is version 3.00 Build 1, which adds the remote control capability, you can find it on the section of the website...
by 5B4AIY
10 Mar 2017 06:18
 
Forum: Juma Discussion
Topic: Problem flashing Firmware
Replies: 19
Views: 6291

Re: PA100-D Input SWR

Hi, Mike, I am posting some swept SWR plots I took of my amplifier. It is perfectly normal for the SWR to be higher when the gain is set to G4. Bear in mind that the presence of an input attenuator will mask SWR problems, and indeed is a common microwave technique for 'improving' the SWR. Provided t...
by 5B4AIY
10 Mar 2017 06:15
 
Forum: Juma Discussion
Topic: PA100-D Input SWR
Replies: 2
Views: 795

Re: Problem flashing Firmware

Hi, Mike, The in-circuit programming connector is J9, and pin 1 is closest to the microprocessor chip, IC9. The error message you are getting means that the PicKit-3 has not detected the presence of the +5V from the board. Note that when you connect your programmer, it will be upside down and so you...
by 5B4AIY
09 Mar 2017 12:26
 
Forum: Juma Discussion
Topic: Problem flashing Firmware
Replies: 19
Views: 6291

Juma TRX-2 Transmitter Signal Levels

Whilst assisting an amateur who is experiencing some problems getting his kit to work, I made some measurements on my transceiver to show the sort of waveforms and signal levels you are likely to encounter. For these measurements, the transceiver was set to 1.8MHz, as even a fairly modest oscillosco...
by 5B4AIY
01 Mar 2017 09:36
 
Forum: Juma Discussion
Topic: Juma TRX-2 Transmitter Signal Levels
Replies: 0
Views: 680

Juma TRX-2 V3.00a Build 24

Juma TRX-2 Firmware, Version: 3.00a Build 24. Build 23 has been removed. As a result of a minor code move to resolve an internal low-level annoyance, I accidentally omitted the offset cancelation in the TX mode, and thus the CW/CWR/RIT offset from the RX mode was still present in the TX mode. My sin...
by 5B4AIY
13 Jan 2017 08:49
 
Forum: Juma Firmware by 5B4AIY
Topic: Juma TRX-2 V3.00a Build 24
Replies: 3
Views: 2446

Re: TRX2 test points

Hi, Whitney, Yes, you are correct, there are no pads on any of the printed circuit boards that are specifically intended as test points. Nevertheless, by examining the various schematics and their printed circuit layouts you will find plenty of places where an oscilloscope probe or a multi-meter tes...
by 5B4AIY
27 Dec 2016 11:43
 
Forum: Juma Discussion
Topic: TRX2 test points
Replies: 1
Views: 1003

Juma TRX-2 v3.00a Build: 18

This build introduces an additional feature to the CW Practice Mode, and finally cures all the switching glitches. CW Practice Mode It is now possible to select the LCD scroll direction. To enter the CW Practice Mode, from the power off state, press and hold the FILTER button, and briefly press the ...
by 5B4AIY
20 Nov 2016 10:13
 
Forum: Juma Firmware by 5B4AIY
Topic: Juma TRX-2 v3.00a Build: 18
Replies: 0
Views: 1213

Re: RX-1 DDS troubles, help appreciated

Hi, OK, now you have the microprocessor working it sounds as if the DDS is not working. If you connect any sort of antenna to the input of the receiver, it is sufficiently sensitive that you should hear lots of signals. If all you hear is noise, this suggests that the synthesiser is not working, or ...
by 5B4AIY
17 Nov 2016 09:59
 
Forum: Juma Discussion
Topic: RX-1 DDS troubles, help appreciated
Replies: 8
Views: 5212

PA-100D Remote Control & Status Monitoring

Build 3 - 26/MAR/2017 Build 1 has been removed, and replaced with Build 3. Whilst playing around with the remote commands I discovered that if the manual band change command was incorrectly formatted, then an erroneous display would result. This version of the firmware uses more robust error checkin...
by 5B4AIY
03 Nov 2016 17:40
 
Forum: Juma Firmware by 5B4AIY
Topic: PA-100D Remote Control & Status Monitoring
Replies: 0
Views: 1452
PreviousNext

Return to advanced search

cron