HR50 with no amplification
Page 1 of 1

Author:  cubix [ Sun Mar 17, 2019 3:14 pm ]
Post subject:  HR50 with no amplification

I have completed assembly and testing of the HR50 all the way through the biasing step. Each mosfet was brought up 150ma sequentially (vr1 @150ma, vr2 @ 300ma, vr3 @ 450ma, vr4 @600ma) as measured with a Fluke 8060a DVOM. The logic comes up as it should and the key mode can be stepped through the changes successfully. Menu comes up fine and all settings are for no atu and no qsk as it has been built. When applying rf with the power off, rf goes through as it should 5 watts in, 5 watts out. When I power the HR50 with the key mode "off", power goes through as it should. When I select COR, I hear the low pass filter relays adjust to whatever band I have selected and I hear the T/R relay working as well. However, the output (meter between HR50 and dummy load) shows a decrease in driving power and there is no increase in output power taking place. The SWR indication is (-.-). I am using known good coaxial cables, power/swr meter, and dummy load. I have checked at rg-316 coaxial connections and solder joints are all good and in the proper connectors for my category of build. My only trouble shooting tools are the meters mentioned. Any suggestions?

Thanks and 73,

Author:  jimveatch [ Sun Mar 17, 2019 7:06 pm ]
Post subject:  Re: HR50 with no amplification

Hi Fred,

We've been working on this off-forum but I wanted to post the resolution for future forum readers. The issue was determined to be T2. The enamel wire was in place and correctly soldered to the board but the end pieces of the transformer were not soldered to their pads on the board so the primary was unconnected.

Fortunately, you were able to send a photo so I could easily identify the problem.


Author:  cubix [ Sat Mar 23, 2019 3:14 pm ]
Post subject:  Re: HR50 with no amplification

Thanks again Jim...moral of story is not to work on building kits when you're tired or distracted...hihi.


Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group