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Reviews For: Juma TRX2A (All band)

Category: Transceivers: HF Amateur HF+6M+VHF+UHF models - non QRP <5W

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Review Summary For : Juma TRX2A (All band)
Reviews: 6MSRP: 499 Euro
UMA TRX2 is a high dynamic range transceiver for SSB and CW, using the quadrature sampling
technique for demodulation and modulation with the low noise phasing method. JUMA TRX2
includes a DDS controlled VFO for a good frequency stability and signal purity. An internal
microcontroller is controlling all functions of the transceiver.
JUMA TRX2 is available as a kit with two kit alternatives:
1. The discrete kit with components and bare circuit boards.
2. The modular kit with assembled and tested boards.
The enclosure is machined and printed in both kit alternatives.
A completely assembled transceiver is also available with the help of the JUMA community.

Additionally there will be two models: The two band model TRX2 for 80m and 40m ham bands
and the all ham band model TRX2A with a general coverage receiver. The two band model can
be uppgraded any time into the all band model by adding related modules. Several add on
option modules are also available for both models.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
DB1JAW Rating: 2013-04-10
simply WOW Time Owned: 3 to 6 months.
the known major brands of amateur radio equipment do surely offer radios with more knobs and similar features but I really enjoy the daily usage of JUMA TRX2A and JUMA PA100-D. Quality of both is excellent and there are no complains from here, once fit with its somewhat different operating structure - SIMPLY JOY DOWN THE LINE :)
AA4PB Rating: 2012-12-21
Still going strong! Time Owned: 6 to 12 months.
Still having fun with the TRX2A after 7 months. I just worked Melbourne, Australia on 20M SSB long path. I highly recommend the firmware upgrade from Adrian, 5B4AJY. Check the Juma forum for the latest version (currently 1.09a). It provides a lot of handy features like band selection, band limit warnings, etc.

I am using an MFJ-1317 switching power supply which is a perfect match.

Earlier 4-star review posted by AA4PB on 2012-05-21

I purchased the TRX-2A kit last November. Finished the final calibration last night. First contact was Slovakia on the first call.

I took the extra time to sort all of the PolyPhase capacitors according to value in order to improve the unwanted sideband suppresson.

This is definatly NOT a kit for the first time builder. All the information, including good pictures, are on the web site but you've got to dig to find what you need. There is no "Elecraft style" step by step instruction for either construction or alignment. I had an issue with tarnished pads on the DDS and main PC boards. Polishing with a pencil eraser worked before applying soldering flux but it gets a little cramped as components are added. I wound up with a couple of disconnected pins on three of the ICs which I had to troubleshoot and resolder. You've got to be careful not to lift pads with too much heat during soldering these pads.

I was missing 5 components (resistors, caps, and an IC) but found them availabe from Mouser Electronics for a few cents each (cost more for shipping than for the parts). I expect that was quicker and easier than getting them sent from Juma. I had an issue with identifying pin 1 on several of the ICs but was able to find the correct location using the excellent pictures on the Juma web site and/or a manufacturer's spec sheet downloaded from the Internet. One IC had no markings at all but from the Mfg found that one side has a very slight bevel and identified pin 1 from that.

DON'T TAKE PARTS OUT OF THE ENVELOPES UNTIL YOU ARE READY TO USE THEM! Many of the caps are unmarked and are identified on the outside of the envelope according to the count of each type in the envelope. If you take them out then you'll have no way to identify them.

This was a fun kit to build and it appears to work well so far. Its not something to rush through however.
F6DEX Rating: 2012-08-01
Very original design Time Owned: 6 to 12 months.
Very original design (same front end as SDR, direct conversion) but fully analogic AF signal processing: polyphase, audio filters… (not SDR).

Extremely well "packaged Kit. Instructions are minimal but all critical instructions for electronic are listed and since there is not a lot of text, you can not miss them!.
I used an LC/meter and all components were checked before soldering. Mechanical assembly and parts could be improved.

Working the first time and easy to align. Kit is not for beginners but practicable even if you don’t have a lot of experience in SMD (my case).

Extremely good audio RX and TX (like old rigs). Selectivity a bit too wide in CW (1000Hz). Sensitivity identical to my K3. Nice to use and 5B4AIY’s firmware adds a lot of feature.
HB9DDS Rating: 2011-12-19
Great TRX for QRP-DX Time Owned: 0 to 3 months.
This is my second TRX2A. It is a very good TRX and a silent RX. All functions are implemented which you need to make successful QSO's. I recommend this TRX to every one who like QRP AND a excellent RX. The TX Audio (electret Mic) is also excellent. If I need QRO Power I can switch on my Expert 1K-FA. I've made with 10W + G5RV contacts to VK, ZL, VU, YB etc....enjoy QRP and DX.

73 de Daniel, HB9DDS

W4YN Rating: 2011-05-23
Great Design & Performance Time Owned: 0 to 3 months.
Built up over winter months, fantastic mechanical layout! Zero wiring except for a few ribbon connectors. RX is very quiet and pleasant audio not harsh at all. Filters have no ringing at all due to SCARF adjustable filter. IQ output for panadaptor monitoring. Also has Serial 232 interface for rig control via logging programs. Easy software upgrades due to 232 boot loader. Have worked lots of DX via SSB and received FB reports using cheap electrolert mic.
WK8S Rating: 2008-02-21
Direct Conversion 10-160 TXVR w/DDS Time Owned: 0 to 3 months.
The Juma TRX2A is a 10-160 Meter SSB/CW Direct Conversion Transceiver with a DDS VFO and receive coverage from 100 KHz - 30 MHz. It's an all surface mount kit that was a pleasure to build with the best organized kit I've encountered. No confusion over what tiny part is what with their system. It's not a beginners kit but was not difficult to build and it worked correctly at power up.

The DC design here provide a remarkably quiet and sensitive receiver. In fact it hears all that my K3 does. The audio is nice and I've received good reports on tranmit too. The Juma's SCAF filter is adjustable and does an excellent job. Like many radios in this price range, extremely powerful adjacent signals can tend to pump the AGC. Many DDS radios suffer from DDS generated spurs but I only found a minor problem in the 21 MHz band which did not interfere or cause any difficulties during a recent world wide DX CW contest.

The Juma has a simple user interface that make it easy to use and offers some surprising features in such a small package like a RS232 port for PC rig control and logging.

I really like this radio and am having fun using it. Unfortunately the Euro to Dollar exchange rate adds a bit to it's otherwise reasonable price. Maybe an American Vendor will pick up the Juma line someday and make it more afforadable. However, I must say, the results I'm seeing from the TRX2A performance make the price easier to accept.