Spectra Remote Mount need to make a repeater

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USGOVTECH
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Joined: Sat May 04, 2002 3:00 pm

Spectra Remote Mount need to make a repeater

Post by USGOVTECH »

In the process of building a link repeater using 2 403-433 spectras, can I get cor/pl detect, ptt, gnd, Tx aud, and Discriminator from 25 pin connector on remote mount radio without control head ? Please help. Thanks.
Will
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Joined: Tue Sep 04, 2001 4:00 pm

Post by Will »

"can I get cor/pl detect," NO. RUS, yes in a way.

Ptt and Mic audio, Yes.

Discr , NO. RX filtered audio Yes.
USGOVTECH
Posts: 230
Joined: Sat May 04, 2002 3:00 pm

Ok How ?

Post by USGOVTECH »

What pins on the 25 pin connector do I need to use to acheive this.

I can get this on the 15 pin connector on the back but I would like to use the front of the radio.

Here are the pins I use on the read.

PIN 8 GND
PIN 11 RX AUDIO
PIN 12 COR or COS (After Installing Mod in Radio on P503)
PIN 13 PTT
PIN 15 TX AUD
Will
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Joined: Tue Sep 04, 2001 4:00 pm

Post by Will »

Control head connector, DB 25. ( 15 pin connector not required)

Detected audio Pin 9 MUST use a coupling cap on all outputs as they are direct from the opamp.

Mic Hi Pin 12
Mic Lo Pin 11

Analog ground Pin 10

Power, Jumper pins 20 & 22

PTT appears on Pin 1, 2, or 4 depending on which interface board you have.
USGOVTECH
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Joined: Sat May 04, 2002 3:00 pm

Post by USGOVTECH »

Thanks Will,

Now where can I get COR/PL DETECT. Generally I pull this from pin 10 on the audio amplifier.
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n1pfc
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Post by n1pfc »

USGOVTECH wrote:Thanks Will,

Now where can I get COR/PL DETECT. Generally I pull this from pin 10 on the audio amplifier.
That's what I do for COR/ PL as well. Pull it from pin 10 on the audio amp and route it to the header on the command board on VIP1_OUT (I forget the pin number, but if you really want it I can get it). make sure VIP-1 OUT isn't programmed for anything in the RSS and you're good to go. Logic is active high if I recall.

Done it tons of times like this on both spectras and astro spectras to be used with ACU-1000's. It makes for a nice one connector installation and no freakish looking pigtails hanging out of the radio and no extra 'vent' holes.

Kurt
I am <I>NOT</I> Hamsexy
Hartley
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COR/PL

Post by Hartley »

Hi,

If Receiver Unsquelch works for you (which I think is the same as the audio amp pin 10), then you don't have to do any internal mods - take either Speaker pin thru a 10K resistor to the base of an NPN transistor (emitter grounded) - gives you an open-collector COR (RUS, really) that works quite well. You can pull audio from the same pin thru a cap if U need it.

73 DE Hartley
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kcbooboo
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Post by kcbooboo »

Just a follow-up to the previous post.

Both speaker leads are driven by the audio amplifier IC. The DC voltage on each one when the receiver is unsquelched and passing audio is about 6-6.5VDC. When the radio is squelched up, the voltage drops nearly to zero, but it may not quite get there.

Somewhere else on the BBS, someone posted a way to make a repeater out of a pair of Spectras, and they powered a couple of small reed relays from one speaker lead to ground. This seems to work, but the audio PA doesn't shut off immediately when incoming carrier goes away. It stays on for several milliseconds longer. Something to keep in mind when you're interfacing it to your repeater.

Bob M.
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