USMC in AFGAHNISTAIN needing YOUR HELP

[justintisdale]

Hey guys,

First off for or any devil dogs oun here, thanks for you service--and YUT!

Alright here's the skinny i got a LOUDSPEAKER CONTROL UNIT: LS-671/VRC
I am wanting to turn it into a portable speaker we can hook up with an Audio Input, 3/8 diameter -- I can cover the power part (2 9Vs attached to the pins that supply power)

but the audio input is my problem im not sure where to connect, due to PUSH TO TALK for the MIC HERE is the schematic of the unit... im thinking PIN B "audio Receive" is wher i would soder the connecting input jack??

ANYONE that could help would be amazing!!

**broken link removed**

 

[dougy83]

Hey Justin,

Sorry my American's not real good, but bear with me. Well, it looks like you got the right connector. J2 is where the handset goes; if you follow the arrows, you can see that 'D - Audio Transmit' goes to the mic amp, so that is where the mic is usually connected (so mic goes between J2D and J2A). The mic amp output goes to J1U, which should probably be jumpered back into J1K 'Fixed Audio'; it will then go through the volume control, then the speaker amp, and finally to the speaker at J1E & F (speaker connects between J1E & J1F).

Don't use PTT as it will mute the speaker when you push it.

All the best.

 

[justintisdale]

so basically i am just jumping the Input jack wire to the MIC circut? if i do this do i ground one side of the wire? the input jack is 2 wire stereo...so im not sure what to do??

 

[dougy83]

so basically i am just jumping the Input jack wire to the MIC circut?

I'm sorry, I think I misunderstood your original goal - if you're connecting a microphone to the thing, it goes where I mentioned before, with the jumper on J1.

BUT, If you're connecting a line-level audio source (or headphone output from an MP3 player or something), then you should skip the mic amp (as your signal is already 'loud' enough) and just connect straight into the 'fixed audio' J1K & J1A and not fix the above mentioned jumper.

if i do this do i ground one side of the wire? the input jack is 2 wire stereo...so im not sure what to do??

You connect the shield to ground, and the left audio signal wire to the amplifier's audio input. If the audio source is from a headphone output or similar, you can connect the left and right channels together before connecting to the amplifier's audio input.

Also note that if you're using those small 9V batteries the thing won't last as long as you want. It's probably designed to run off a truck battery or something.

 

[justintisdale]

alright i am following you kinda... here is a link to the audio cable i am trying to use as the audio input

hama.co.uk | 053206 Hama Extension Cable, 3.5 mm jack plug - 3.5 mm jack socket, 2.5 m

I have the "two double wire" stripped back and one side is *WHITE with copper around the outside and *RED with copper around the outside. Im guessing the copper is just a sheilding to prevent interference?
So how do i connect it with these??? Should i twist them together and put to the MIC AMP? J2D? or is there a better way? (sorry im asking so many questions-- i can read the schematic but and have a fairly good knowledge about Electronics, but we have limited resources out here so i am making sure that i am not gonna blow this thing or the ipod or ipad up..." thanks again!!

 

[dougy83]

USMC LOUDSPEAKER?
Hey i was the guy you are trying to help with the LOUDSPEAKER.

I posted but its been 2 days and the update hasn't been approved by a moderator yet. due to the link i put in showing you the audio headset jack i am trying to wire up....

i have a 3.8mm input jack made by hama- i stripped the wires back and i have 1 *white wire with copper wire surronding it (i guess it serves no purpose) and 1 *red wire also sourround by copper wire--- where do i need to hook them up too?? should i just twist them together since the speaker is mono (i believe)

The 'copper wire surrounding it' is the shielding & also the ground connection. The white wire is the left channel audio, the red wire is the right channel audio.

So, the 'copper wire surrounding it' goes to the amplifier ground and the white goes to the the amplifier audio input. You can connect the red to the white if you want, or just leave it disconnected.

 

[justintisdale]

sweet alright so now on to power? what do you think is the best to use? a few rechargable AA or AAA batteries linked together? and if so how what PINS WOULD I GO TO?

Positive to J1D (power relay) and then the negative to J1A (ground)??

If i did the J1A with ground would that not send votage back across the line to INPUT jack wire and ultimatley to the IPOD we would have connected??

 

[dougy83]

I would go for a 24V truck battery (which is what it's designed for I'm guessing) on a trolley so you can drag it around...

I don't know anything about your amp, but the thing looks like it takes 24V and drops it down to 18V & 9V. So if you're using 1.5V cells, you'll need 16 of them. The bigger the better (obviously a trade off between operating time and portability).

While I don't know for sure what CB1 is - I'm assuming it's a circuit breaker, Power would normally go in J1B only to return out J1D which would be fed back into J1C - this just allows the circuit breaker to do its thing. So... just bypass that junk and connect the positive to J1C (negative to J1A).

The battery negative and ipod shield end up being connected together, yes; ground is common for all the circuits here.

I'm guessing you're just doing this for kicks - otherwise I'd suggest just buying a premade rechargeable ipod loudspeaker for a few bucks - it would sound better, be smaller, cheaper (16 batteries will set you back a bit) and last longer on a charge.

You might want to connect the thing to a power supply & speaker before purchasing any batteries for it - just to check if the sound quality & loudness, etc. is acceptable.

 

[justintisdale]

yeah we have limited resources out here in afagahnistan so i have to work with what i got..lol thanks for you help! im still trying to figure out the battery situation...

 

[dougy83]

Oh right, sorry, I seemed to miss the point that you are still in afganistan; I thought you must be returned.

Well, in that case, best of luck finding anything that'll work!