VIC 1 in the M37

[ke6rwj]

Yea i did some tests last night on that, i posted the basic diagram on my wiki, not a solution though.. it seems that the mute circuit isn't being activated, not sure if its due to low voltage (12 instead of 24) but i cant really test that just now.. ill have to integrate one of my isolation modules to do that.

but i noticed that even with the RX audio line disconnected it did the same thing. the only thing that stopped the feedback is disconnecting Pin S (TX Return line) from the setup, but that provided low audio with a noticeable "buzz".

It was noted that this outputs low tx audio no matter what, so it just maybe that the solution is to disco S, and fix the buzz..

if i find a solution ill post i here as well as the wiki.

BTW NM gives me flashbacks, went to school in Roswell... AAHHHHH!!!

the buzz on transmit is due the low voltage of using this with 12volts Vs, 24.. when i run this with 24 volts the buzz is gone...

UPDATE - Turns out i had some bad connections that introduced the buzz, it was fixed when i resoldered connections and shortened cables.. So this does work for full TX and RX into a Civi Ham radio. the only remaining issue is that the TX audio is low, but i think i can fix that also..

more to come.. Details on wiki below..

http://radionerds.com/index.php/LS-671

 

[ke6rwj]

Using the LS-671 to remotely Power On/Off any 12volt radio

final installment in the quest to fully integrate the LS-671 into civi radios...

LS-671 - RadioNerds

The LS-671 has some interesting features that allow it to remotely turn on/off radios. for example, mounting a CB, GMRS, AM/FM under the seat and using the LS-671 Power switch to turn on and off the other radio. Of course you would have remote volume control receive audio and transmit functions...

Features
Remote On/Off of the radio by the from power switch on the speaker
Volume control for RX
Transmit for TX

Known Limitations
if you leave the speaker on, and manually turn off the radio, the speaker will still draw from the battery. (even in military radios it does this)

This uses a simple 12volt relay to connect the 12volt power line of the radio, this is accomplished by Pin D of the Ls-671 where voltage is applied when the speaker is turned on. You need to use a relay because its unlikely the speaker will be able to handle the power draw of the radio (especially in transmit). You can use any 12volt relay, the one listed is a SPDT but i also used a DPDT from radio shack (OMI-SS-212D)

 

[serial14]

which connections were bad? Was it the main connector that was dirty? or was it in your own cabling? My LS671 is certainly surplus along with my cable, I had never considered cleaning the pins of the cable, but perhaps I should.

I'm curious on your comments about not hooking up the 'S' pin. Does the LS671 internally couple this to GND? Is the signal out of pin 'U' bipolar when compared to ground?

 

[ke6rwj]

which connections were bad? Was it the main connector that was dirty? or was it in your own cabling?

i spend so much time hacking on the Vic1 and related stuff that i have a whole second setup (AM-1780, C-2298, RT524, civi radios) on my workbench with cables routed around tool boxes to power supplies etc. The line running to the civi radio was laying against a 110v power line picking up noise.

I removed this cable and hooked the speaker directly to the radio via a DB9 pigtail that is wired in. There are some details about that on my wiki, but essentially its a hard wired DB9 plug that has RX/TX audio, ptt, 12v and gnd so i can just hook it to anything wired on that standard, which for me is everything.. funny mics, speakers, TNC, Data units, VIC intercoms...

My LS671 is certainly surplus along with my cable, I had never considered cleaning the pins of the cable, but perhaps I should.

im not using the factory cable at all, i sacrificed an old and busted CX-4723 and used the connector to make my own cable.. then i didn't have to worry about crossed pins and such.. which is the issue with pin S, more below

I'm curious on your comments about not hooking up the 'S' pin. Does the LS671 internally couple this to GND? Is the signal out of pin 'U' bipolar when compared to ground?

Im not sure what it does in the LS-671 with the wire on Pin S, it says its TXMIT RTN, and shows that Pin S, is connected to PIN A in the cable normally used with this unit, since im not using the cable it wasnt an issue. It does lead me to think that hooking that to ground should be ok, but clearly its not. I have nver found a *real* schematic on this unit, only poorly copied home drawn junk that are clearly wrong, and a block diagram. Until we see a schematic, its hard to say. I'll be doing more on this point later though.. i still need to fix the low audio problem.

As for Pin U, i assume its getting the ground for the signal from the chassis/common, but that isnt ideal either.

what i do know now is that if you hook Pin S to ground, it will squeal like a demon, but if its off, it works fine, although the audio is a bit low.