No, what I'm saying is, your 949 is wired differently...
IF you can disconnect the Mic and it stops the audio from the RX to be heard, then you have work to do
For the Pin 1 and 4 shorts together, ALL THE TIME -
INSIDE the Mic Plug, even without the Microphone cord attached, it lets you hear RX all the time until you key up (Short Pin 1 to Pin 3)
Update::::: so weird as hell. I’m thinking hell let’s try the stock galaxy mic that came with the 949. My Skythumper I use on all my radios is 4 pin as well. Wouldn’t you know the galaxy mic plugged in I have normal lively recieve and I can here it well. WTH would my 4 pin skythumper be wired differently??? It’s paired with my comp cobra 29
Here's how it works in the 949...
8 V is applied thru the RX/TX switching...
In an earlier Galaxy, you have this method...
Pin 4 is left open ...everything switching related is done thru Pin 3...
In a Uniden PC-122 SSB radio - Pin 1 and 4 are shorted at the Mic Plug...
So, I was in error earlier - it doesn't short, it stays ACTIVE until you let up on the key and then Pin 4 DROPS allowing Q36 to turn on and let Audio Amp work (Un-Mute).
To Add:
To solve this problem you'll need to research the Mic you want to use, and the Radios own wiring.
Now you know that Pin 4 is powered thru the 8V lead-in at the Mic Plug - WHEN you key up, It has power, so any or many "talkback" mics may or may not inteface well with this scheme - because of the power feeder.
So if you have a POWER mic that "opens" pin 4 and Ground (Shorts) Pin 4 to Pin 1 (Ground Shield) on Receive, this could work.
But if your Mic uses Pin 4 as a method of talkback thru the GROUND at the Speaker Return - this might not work.
- For the fact - that OTHER Cobra and Uniden Mic's would otherwise leave open (Speaker Return) which in these radios it's power (audio) would route instead to Final and Driver - leaving Speaker unable to complete a circuit unless Pin 4 gets grounded to make the Speaker circuit complete.
- This is where Talkback in some radios work like it does, the Speaker IS ALWAYS connected - but the LAST leg of it's journey goes to the Mic so that places a resistive element in the Speakers Return wire - this forces the resistor to complete the circuit . It is a Dead short across the SWITCH (Wires that go to Pin 1 and Pin 4 in the Mic handset) when you're not keyed up.
- Unkey the mic and wham, audio is heard thru the speaker - just a simple Pin 1 to Pin 4 Short to Ground and you completed the Speaker circuit.
That's why the Cobra Uniden radios that when you remove the Mic, the speaker can't complete the circuit - no speaker - no noise, but has RX you can see on the meter - just can't hear it.
And it's also why Some Talkback mics' use this feature - they insert a variable pot across Pin 4 to Pin 1 ... Pin 1 is the Mic's ground lead to the Radios Ground and Return. -
Volume is adjusted by different methods usually by a resistive element
- - thru a variable resistor. This allows you to complete the Speaker circuit, but have a variable resistance to raise or lower the power - or volume - when you're keyed up and talking
- - Pin 4 would normally be open, but a resistance is there now, allowing some Audio power still present in the Speaker line, to flow thru the speaker circuit and return to ground via Pin 1 Doesn't apply to 949
- The Pin 1 to Pin 4 short in the Mic switch places the switches shorting contacts as a dead short across the pot, then the full return path of least resistance is restored to complete the speakers return to ground and you hear audio thru that speakers' circuit. Again, does not apply to the 949 - uses it's own Talkback circuit.
The method described just above, will not work on the 949 - it uses a separate Talkback circuit that when it's engaged, it routes thru a simple pre-amp to the Audio Amp. Remember in a 949 the speaker line is connected to that Audio Amp all the time - it simply turns off mute (Q36 and it's Diode) and allows Mic audio from the Mic amp to route thru a potentiometer (your volume pot or Talkback pot) and the pre-amp Q42 - The Audio Amp is on all the time.
This is why I want you to investigate your 949 - if mods were done, no matter what we do, we can't provide any help until we know what you have had done in the 949 so we can then find you a workaround.
I'm not sure if anyone else is experiencing this but due to either hacking or CME's occurring - our internet here locally is spotty and I'd be typing along, the board / forum doesn't seem to get all my typing so I have those moments where I have to go back in INSERT the missed dialogue/paraphrase - Irritating...