G2 Ultra Distrorted Audio et al

[K0PJ/9]

Good morning,

First off, I have read every post on G2 distorted audio. Thank you for posting. None of the non-circuit board surgery fixes have worked for me.

I ordered my first G2 Ultra (with display) 1 year ago. The radio arrived mid-summer and had distorted audio right from the start. This happened while using the radio with a commercial 3-pin XLR to TRS connector and a Heil PR-40 and INRAD microphones. Distorted audio and hum was reported when using the radio as is, as well as thru Thetis.

The first radio was returned to Anan and I received a replacement radio in the fall.

I have had the same issues with the 2d radio. On air reports are a strong low frequency HUM (100-400 hz) and WARBLE across the audio spectrum. This happens with and without a microphone connected to the radio. I can also see this on the screen and hear it on an independent radio. I have diligently worked on this issue for the last 5 months.

Here is what I have tried:

* Connecting the TRS cable plug to the ground lug of the radio.
* Adding ferrites inside the radio as described as one of the fixes.
* Trying a Heil Headset with an adapter using the front and rear MIC jacks (and changing the software).
* Trying to use the equalizer to filter out the hum.
* Added common mode choke prior to the antenna input of the radio.
* Replaced all coax and beefed up all grounding and bonding.
* Connected the Radio directly to the computer via a shielded Ethernet cable.
* I run the radio at 8 watts output. I am not over driving anything and all audio levels are set correctly.
* Changed DC cable to a filtered cable connected directly into an Astron 35M. The Astron is connected to a Filtered AC main.

On a side note, I have an SPE produced cable for the G2 and have yet to get the amplifier to track frequency. Again, I have read the posts.

I'm willing to try other ideas before sending my 2d G2 Ultra out for repair.

I have an Expert Electronics MB1 that works without issue on the above system.

Thanks,
Greg

[w-u-2-o]

If all of your problems are centered around using the balanced mic input (erroneously called the XLR input), then:

With the possible exception of the ferrites, which have worked for some people but not on all bands, nothing you have tried will solve the problem, and you should already know this if you've read every post.

There is only one fix that works for the balanced mic input, and that is to either modify the preamp board to use an regulator or obtain a preamp board with the regulator on it and swap it out. I suppose another way to do that is to send the unit back for "repair", i.e. the board swap. Refer to this topic:

viewtopic.php?f=48&t=4863&start=30#p28793

With any source of audio (balanced, unbalanced or PC-sourced), you also need to perform the "fix" described in this topic and is quite easy:

viewtopic.php?f=48&t=5307

Either change the jumper config. or just put a 50 Ohm terminator on the 10 MHz input (and to be safe every other port except the XVTR port). Even better, put an external GPSDO on that port

If you are running Thetis and not piHPSDR, then IMHO the best solution is to use PC-sourced audio via a high quality, ASIO capable, USB sound interface. You'll still need the jumpers/terminator on the 10 MHz input.

[n2gq]

Curious is this during high-power or just radio power?

[K0PJ/9]

Thank you. My hum and distorted audio happens at all power levels and on all bands, with or without a microphone attached to the rear XLR/TRS connector. I did try to use a SMA to SO-239 adaptor to a 50 ohm dummy load on the 10 mHz reference port. At 5 watts out, and listening to my signal on my Grundig Satellit 800 receiver, I clearly hear the hum, "warble", distorted audio regardless of mic gain level. My antenna is located 200 feet away using underground 1/2 hardline. I'll look into the regulator board though most likely beyond my capabilities. Greg

[K0PJ/9]

PS - if anyone would like to hear "on-air", I'd would be up for a sked. Perhaps that asssist in clearing up any confusion on my end. 73, Greg

[w-u-2-o]

One more thing to try in order to help debug the issue, would be to use a simple USB microphone attached to your PC and use VAC to transmit with that.

[K0PJ/9]

Scott,

Thank you. To make matters worse, my Thetis signal path failed this afternoon, meaning, the radio is connected but no signals heard. Signals OK as a stand alone radio with display except for the aforementioned audio issues.

I'm really trying to get my Anan to work.

73,
Greg