No Mic input when plugged directly to the radio

[W1SPS]

I'm just about ready to give up on this radio. I've had it over a week and cannot get the radio to acknowledge any input from my Sennheiser MD-421-ii Dynamic Balanced XLR Mic when plugged directly into the radio. I have a Balanced XLR to TRS 1/4" cable plugged into the XLR (TRS jack) on the back of the radio. When I push my PTT button (Which goes to a 1/8 to dual RCA Splitter in the PTT IN/OUT jack) One RCA goes to my AMP, the other to the PTT switch. The radio will key, but there is NO input from the mic. However, If I press TUNE the radio does make a tone for tuning.

It's almost like the front and rear mic jacks aren't hooked up.

I tried using the radio through a Focusrite Solo sound card. I did get output from the mic when I was running through virtual cables, but I don't want to do that yet. I want the jacks on the radio to work first till I get used to the radio. I'm starting to think there is something wrong with this thing. The is no way in hell plugging a mic directly into a radio could or should be this difficult.

Rich
W1SPS

[w-u-2-o]

Dumb question: did you enable the correct mic input in Thetis setup?

[W1SPS]

I thought I did, but if you got a screenshot I can verify that.

Well to be more clear, I only saw a thing for selecting the mic being used when I ran the radio software on the screen of the radio.

When I run Thetis on my PC I did not specifically see a selector to use the front or rear mic jack. The only thing I saw specific to audio in and out was in the Audio tab asking to enable VAC (which I would rather not use for the mic).

OK, now In looking through the radio manual further (In a place I would have never suspected):

4.1.1 p2app Command Line Options
To run for normal use:

./p2app

Or it can be run as ./p2app <optional arguments>
Where <optional arguments> can be:
-f <freq in Hz> Turns on DDC test frequency source for development
-i saturn Identifies board as “Saturn” (default)
-i orionmk2 Identified board as “Orion mk 2”
-m xlr selects XLR microphone input
-m jack selects 3.5mm microphone jack (default)
-s skip checking for “x” button to exit (used when run at startup)
To exit: type x<enter>
(note no text is displayed as you type; just do it!)

The most likely command line option is to select the balanced XLR input. Options to select this from
the client application have not yet been implemented. To run p2app with XLR selected, type

./p2app -m xlr << So am I to understand that the ONLY way to activate and use the XLR jack is to run p2app in a command line????

[w-u-2-o]

I don't have a G2. At one time the only way to get the balanced input to run was to manually edit the Pi startup script to add the command line switch for p2app. However, I believe that this function is now supported in Thetis, although on what setup screen I'm not certain.

@laurencebarker what's the word on this?

[Bagabonz]

I have the same issue on my G2. The only mic inputs I can get to work are the 3.5 mm. I've changed it in the standalone mode to xlr with no luck. I usually only run Thetis but I do like the ability to run it standalone as well. If a mic selector has been added to Thetis I'm not aware of it.

[Bagabonz]

OK I haven't tried this yet but in Thetis under Setup>General>Hardware options> xlr is an option.

[W1SPS]

I don't see anything that specifically says XLR

I see a mic / bias / PTT and Alex (whatever that is)

[Bagabonz]

For clarification I am on the latest version of Thetis.
Under hardware options In the 4th row down I have-

Input xlr or 3.5 mm and Alex

Be sure you have G2 selected in Radio Model.

[W1SPS]

That's odd. I just downloaded Thetis 2.10.0.0 and I know Anan-G2 is selected.

[Bagabonz]

2.10.3.6 is the latest version

[W1SPS]

WTF

You know the way github lists their releases is assinine.
But in looking at the release notes I don't see a mention about XLR anywhere. So I guess I'll see when I get home.

[w-u-2-o]

Just in case you are in the wrong repo: https://github.com/ramdor/Thetis

Announcement and discussion right here in the tacked thread at the very top of the Thetis sub-forum:

[attachment=1]Capture.JPG[/attachment]

Git is very clear about releases when used properly, as it is here:

[attachment=0]Capture.JPG[/attachment]

[W1SPS]

Ok, I got it. wow they added a LOT of stuff. I did check the XLR setting and I put the force XLR in the command line for p2app. The mic now works but the audio I'm told needs a lot of work. Very Hot and allegedly had an "echo'ey slap back". If I could see someone's settings that is using a direct mic connection my hopes is it will get me in the ball park.

[laurencebarker]

There is an updated version of the manual that says both Thetis and piHPSDR have controls to select XLR input. It can still be selected from a command line switch, too.
Have you run the audiotest app to record an audio segment and play it back?

[w-u-2-o]

Ok, I got it. wow they added a LOT of stuff. I did check the XLR setting and I put the force XLR in the command line for p2app. The mic now works but the audio I'm told needs a lot of work. Very Hot and allegedly had an "echo'ey slap back". If I could see someone's settings that is using a direct mic connection my hopes is it will get me in the ball park.

Make sure you have the mic boost setting turned off in Setup > Transmit.

Echo is almost always a symptom of RFI.

A lot of folks have had difficulties with this interface. See the lengthy thread here:

viewtopic.php?f=48&t=4863&hilit=preamp&start=30

That link will take you right to Laurence's post where he provided us with a PDF file of the schematic, and a modification, but you can read the entire thread, of course.

I don't know if that mod has made it into G2 production units or not.

[laurencebarker]

My understanding is that mod has been in all production radios for several months. So the RFI-like problem (which was definitely real before) should have gone away. I've no idea when it was adopted into production though.

It wasn't strictly RFI, but had exactly the same effect. High current draw resulted in ohmic loss on the power cable; that modulated the microphone input.

[W1SPS]

Well.... Here we are. I had the XLR forced in the command line of p2app. I also downloaded the newest Thesis and set the mic for XLR. Seeing as I didn't need the forced XLR on p2app I removed that (or rather put it back to stock). I can get audio from the mic now however I cannot get enough modulation to drive the amplifier sufficiently (Ive tried it with +20 on the mic on and off). When it is on I get this horrendous echoey feedback and when it is off I have very low audio drive. Even when I get my settings to reach 0db there is a echoey slapback (this is how it was described to me by someone on the air). I have bypassed the amp, that does not help. I can hear the echo on the monitor but I had heard that that was common on these radios (I sure hope that isn't true because that makes the monitor kinda useless).

So... once again... I'm out of Ideas. Is it possible there is something wrong with the audio circuit and if so how the heck would you check that?

Rich W1SPS

[w-u-2-o]

Did you take a look at the thread I posted a link to?

If not, take a look at this specific post: viewtopic.php?f=48&t=4863&start=30#p28793

You'll probably want to take a peak inside and see if you've got the latest revision balanced mic input board with the ferrite and the 78L05 regulator.

[W1SPS]

Good lord, If I have to take apart a brand new radio to make sure it has the newest/correct parts in it, they can have it back. This isn't RFI and if it is, the RFI doesn't affect my SunSDR2DX. This is effing ridiculous.

There is a ferrite on the XLR line inside the unit just after the XLR input.

How do I know if I have the newest board. I see a Anan-G2 Pre Amp board, I see no revision number on it.

[Trucker]

If you are having this problem in Thetis, check to see if you have the Monitor button activated on the main Thetis display. That could be the source of the feedback you are getting.
James
WD5GWY

[W1SPS]

If I monitor myself with "MON" I can hear the feedback if +20 is on, But even with it off and at almost any usable audio level lower I hear an echo. If I shut "MON" off ant talk to someone I get the same report. I have ferrites on everything, station is very well grounded (check the QRZ pics), I even put an extra ferrite on the XLR line inside the radio. No effect at all.

Again, I have NONE of this prob with the SunSDX2DX. Same mic.

This HAS to be something with the radio. I'm not doing anything unorthodox here.

[w-u-2-o]

I hate to suggest additional work on your part, and I agree that things should work right out of the box and not be so difficult. Nevertheless, here are a few things that might help narrow down the root cause of the problem.

- Use the two-tone feature and ask people on the air if it sounds clean. This is quick and easy and will identify if the problem is in the mic audio chain (both hardware and software) because the two-tone signal is generated after audio processing.

- Use VAC. You can do this with a simple USB mic or headset plugged into the Thetis PC. In the Windows Sound Control Panel set the mic sample rate to 48KHz. Keep VAC settings simple (i.e. don't shoot for low latency): MME driver, 2048 buffer, other buffers on automatic, force box checked. If this works OK then we know the problem is associated with the balanced preamp input.

OR

Switch to using the 3.5mm mic jack. If you disable hardware PTT input in Setup > General you can often get away with almost any mic plugged in there, just use the MOX button for testing. However, if you want hardware PTT anything you plug in there must be wired correctly, i.e. no part of the mic element wiring may touch the PTT contact (usually set to the "ring" contact). Again, if this works then we know it's the balanced input that is at fault.

- Take a close-up photo of the balanced preamp board and post it here. This might help us determine if you have the board with the additional regulator. Again, as discussed in the above referenced thread, this is a known design deficiency in early revision boards that can cause echo.

[W1SPS]

Ok, here's the thing. I don't want to use VAC as I hear that sounded like crap too.

I don't know how to post a pic here as I don't have a URL to send it from.

If the answer to this ends up being, well, you just can't use your XLR input. Then my answer is, (directed to Apache Labs) take your piece of crap radio back.

[w-u-2-o]

Ok, here's the thing. I don't want to use VAC as I hear that sounded like crap too.

If that's truly the case then you almost certainly have an RFI problem that is affecting the G2 and/or the mic setup you used with VAC.

I don't know how to post a pic here as I don't have a URL to send it from.

Look below the text editor window and you'll see a section with two tabs, Options and Attachments. Select the Attachments tab and click "Add files". If you want to get fancy, click in your post, then click "Place inline".

If the answer to this ends up being, well, you just can't use your XLR input. Then my answer is, (directed to Apache Labs) take your piece of crap radio back.

I don't blame you one bit. However, you haven't done any of the tests that were suggested, so we don't know for certain. One thing is certain, though, and that is VAC works perfectly. If you can't get VAC to work it is not a problem with the G2 or Thetis.

[W1SPS]

ok, hooked up the VAC yet again. There is a definite echo. Not a feedback, but a straight up echo 2-3 seconds apart. That ain't RFI.

This radio is hosed. I want a new one or my money back.

[w-u-2-o]

ok, hooked up the VAC yet again. There is a definite echo. Not a feedback, but a straight up echo 2-3 seconds apart. That ain't RFI.

This radio is hosed. I want a new one or my money back.

AFAIK there is no failure mode of the any openHPSDR architecture hardware (Apache, Hermes Lite, whatever), firmware, or software that can cause an echo via VAC, other than RFI related. 2-3 seconds is rather lengthy, echo is normally heard about 100 to 200 mS, depending on how much audio processing is enabled.

Have you tried transmitting into a dummy load? Did you try the two-tone test as suggested? Did you try the audiotest app as Laurence suggested?

Also, while this is a great place to get things off one's chest, it's not a good place to ask for repairs, replacement or refunds. Apache employees monitor this forum very rarely, if at all. You should contact them directly if that's what you want to do.

[W1SPS]

I'm just speaking where this is leading to. I don't care what they monitor. This is a 2-3 second slap back echo. It is NOT RFI. Everything I have hooked up is exactly the same as my SUNSDR2DX and it doesn't have these problems.

This radio is a piece of garbage and if they don't take it back I reckon we can check with the FTC.

Such a shame, because the receive really is quite excellent.

[w-u-2-o]

Maybe you've got a lemon, maybe not. There are plenty of other folks who don't think it's garbage.

[W1SPS]

Well geez, maybe their functioned out of the box.. Who knows.