Repeater - help

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watson123
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Joined: Fri Feb 21, 2003 11:36 pm

Repeater - help

Post by watson123 »

Has anyone built a repeater from two maxon sm4450 mobiles and a zetron repeaterman model 37 controller?
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n_zero_ndp
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Re: Repeater - help

Post by n_zero_ndp »

watson123 wrote:Has anyone built a repeater from two maxon sm4450 mobiles and a zetron repeaterman model 37 controller?
I have made a repeater from two 4450's before but did not use a repeaterman controller. Having trouble locating your connection points?

Ken
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vcaruso
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Post by vcaruso »

I could also use instuctions for doing this if you could.
watson123
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Post by watson123 »

Yes Iam having trouble understanding where to connect everything. I have the zetron manual but I do not know where to connect to the 4450's. I will post some more detail later in the afternoon about what wires fron the zetron go where. Hope someone can help

Thanks
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n_zero_ndp
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Post by n_zero_ndp »

Well, it's been several years now...
But as I recall - all connections except for the COR (& possibly the disc. audio - or whatever rx audio can be found) were on the mic connector.

The TX radio needs connections for PTT, TX Audio & ground.

The RX radio needs connections for COR, Discriminator Audio & ground.

I don't have a schematic at my disposal anymore, so if someone could provide some help there I'm sure we could figure it out quick. Depending on what logic level you need for COR, you may have to build a logic inverter. The Zetron will probably accept + or - COR logic (2 seperate connections are provided on the Zetrons as I recall).

Sorry for all of the work from memory. My memories may not be so close to the truth......

Ken
watson123
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Post by watson123 »

Ok Ken This is what I have

From the Zetron manual the wiring pin layout.
1 - 12 volt
2 – Ground
3 – Discriminator
4 – Ground
5 – TX Audio
6 – Not used
7 – PTT
8 – Ground
9 – COR
10- CTCSS

The following are the instructions.

1 – Connect the power supply positive supply lead to pin 1, connect power supply ground lead to pin 2.
2 – Connect a chassis ground wire from pin 2 to the chassis ground of the transmitter/reveiver.
3 – Connect a wire from pin 7 PPT to the PPT input of the transmitter. This output is a FET and pulls to ground when PPT is activated.
4 – Connect pin 5 to TX AUDIO to the microphone input of the transmitter. Shielded cable must be used for this connection. Connect the braid to pin 6 GND.
5 – Connect pin 3 DISC to the receiver discriminator output. Shielded cable must be used for this connection, connect the braid to pin 4 GND
6 – Connect pin 10 TONE OUT to the direct modulation or CTCSS tone input of the transmitter. Shielded cable must be used. Connect the braid to pin 8.
7 – The COR, Connect pin 9 to a carrier indication point in the receiver.

They said it was easy to connect two mobiles to create a working repeater. This sounds like a foreign language to me. This is not easy.
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n_zero_ndp
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Post by n_zero_ndp »

watson123 wrote:Ok Ken This is what I have

From the Zetron manual the wiring pin layout.
1 - 12 volt
2 – Ground
3 – Discriminator
4 – Ground
5 – TX Audio
6 – Not used
7 – PTT
8 – Ground
9 – COR
10- CTCSS

The following are the instructions.

1 – Connect the power supply positive supply lead to pin 1, connect power supply ground lead to pin 2.
2 – Connect a chassis ground wire from pin 2 to the chassis ground of the transmitter/reveiver.
3 – Connect a wire from pin 7 PPT to the PPT input of the transmitter. This output is a FET and pulls to ground when PPT is activated.
4 – Connect pin 5 to TX AUDIO to the microphone input of the transmitter. Shielded cable must be used for this connection. Connect the braid to pin 6 GND.
5 – Connect pin 3 DISC to the receiver discriminator output. Shielded cable must be used for this connection, connect the braid to pin 4 GND
6 – Connect pin 10 TONE OUT to the direct modulation or CTCSS tone input of the transmitter. Shielded cable must be used. Connect the braid to pin 8.
7 – The COR, Connect pin 9 to a carrier indication point in the receiver.

They said it was easy to connect two mobiles to create a working repeater. This sounds like a foreign language to me. This is not easy.
OK, just for starters since I don't have a 4450 schematic:

RJ11 mic jack of TX radio (I just soldered my wiring onto the PCB where the mic jack is - makes a cleaner install as you can run your wiring thru the back of the radio)

(pin 2) ---- PTT --------> #7 on the Zetron
(pin 5) ---- ground ----> #2 on the Zetron
(pin 3) ---- mic hi -----> #5 on the Zetron
(pin 6) ---- mic low ---> #6 on the Zetron


In the case of the TONE OUT connection on the Zetron, this can be left unused. Set your TX radio to encode the CTCSS/DCS of your choice & set the Zetron to encode NO TONE (carrier squelch). Hopefully, we can find a spot on the RX radio to pick up the COR activity with TONE ONLY - otherwise anyone will be able to key your repeater with carrier squelch (NOT A DESIRABLE SITUATION UNLESS IT WILL BE A HAM REPEATER)

Until I can get a schematic in my hands, I have no idea where to wire up the RX radio for COR or discriminator audio.

Ken
watson123
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Post by watson123 »

n_zero_ndp

I found this information and do not know if this will help.

Pin 1 Audio in
Pin 2 TX Tones
Pin 3 Busy/Squelch
Pin 4 Call
Pin 5 Monitor
Pin 6 PTT in
Pin 7 RX Audio in
Pin 8 Alert Tone Out
Pin 9 Call LED
Pin 10 Mic Control
Pin 11 Audio Mute
Pin 12 TX Enable
Pin 13 Ground
Pin 14 8V
Pin 15 No connection

Like I said I do not know about this information. I just found it and it said maxon wiring pin outs.
INDI12
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Joined: Sun Jun 27, 2004 5:13 pm

sm4450 schematics

Post by INDI12 »

I have a complete service manual for these radios. i have scanned the schematics and have them available for you guys. i would also like to combine 2 of these radios for a repeater. e mail me for the scans.. at
indianajones12@hotmail.com
jerry
440roadrunner
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Joined: Sat Aug 21, 2004 10:52 am

Post by 440roadrunner »

Did you guys get this straightened out? I have some of these, and a Zetron 37
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