Mitrek pl not Functioning

fxbuilder · Post by **fxbuilder** » Mon Jun 26, 2006 10:14 pm

I've got the reed pl board in place. I get voltage out of the audio mute (Pin 5) when it detects a pl. My problem is that the radio passes audio regardless of the pl board being in place or not. I believe the hang up box to be in correctly but that doesn't seem to make a difference whether the mic is in place or not. This is the last step in finishing my repeater. I'm using the CSI 8200 for the controller. It keys the radio regardless of pl. It asks for audio off the detector, PTT, and Transmit audio. I'm assuming that the pl board doesn't allow signal to pass out the detected audio line? Hence no pl input to the controller? Newbee here so please forgive me if I'm missing something here.
My second problem is that if I go a half mile away from the repeater it will kerchunk but not pass audio. Audio is fine within that half mile, Any suggestions here? I've tuned this radio twice to make sure all was good. Help please! Thanks in advance.
Craig

Will · Post by **Will** » Tue Jun 27, 2006 1:10 am

The Mitrek PL board only mutes the audio stage before the speaker amp.

The discriminator audio, on pin 11 is NOT muted and goes out to the volume control. Pin 16 gets grounded to put the receiver in PL mode thru the PL board, and the PL board mutes the RX audio stage.

You need to get a PL Indicate signal out to your 'controller' box.

If the Mitrek was stock, there is a point that can be used for RUS, which is Receiver Unsquelched Signal. RUS has both the carrier squelch and PL indicate signals.

fxbuilder · Post by **fxbuilder** » Tue Jun 27, 2006 6:43 pm

Thanks for the info. The pl board is still not muting the audio even at the speaker stage everything comes through. Hangup box is in place and all. I'm missing something simple I'm sure. Any other suggestions?
Thanks
Craig

Will · Post by **Will** » Wed Jun 28, 2006 1:50 pm

Craig,

IS pin 16 of the control cable accually getting a ground? Here is where your multineter comes in, measure the voltage on pin 16.

fxbuilder · Post by **fxbuilder** » Wed Jun 28, 2006 3:34 pm

I'll check to make sure the ground is good. Any ideas about losing audio 1/2 mile from the radio, but can still kerchunk from farther away?
Thanks
Craig

kf4sqb · Post by **kf4sqb** » Thu Jun 29, 2006 8:42 am

Check the interface board (where the control cable plugs in) to main board connector. They are notorious for getting dirty contacts, and showing strange problems. I can't say that it could cause the 'range' problem you are having, but I have definately seen it cause the squelch problem you are having.

Larry Page · Post by **Larry Page** » Thu Jun 29, 2006 9:23 am

The range problem sounds a bit like some of your transmitted RF is getting back into your receiver. As a result, the receiver may be locking onto the transmitter's carrier rather than your radio's carrier. Might double-check the tuning of your duplexer or cavity adn make sure your antenna is well-grounded. This also might be caused by your antenna being too close to the repeater in your trial setup, allowing transmitted RF to be fed back into the system on the receive side of the duplexer.

Regards,

fxbuilder · Post by **fxbuilder** » Mon Jul 03, 2006 2:51 pm

Thanks for the help. The antenna is 13 ft above the repeater and duplexer which is on a small hill. I can kerchunk the repeater from about 2 miles as the crow flies but stoill not pass audio. I don't have any good tools to tune the duplexer. I guess maybe it needs a tighter notch? How do I go about checking this.
Craig

Will · Post by **Will** » Mon Jul 03, 2006 11:51 pm

Craig,

Just type in "Duplexer+alignemnt tuning" in the Search box.

Honestly there is a ton of posts here allready on duplexer alignemnt aka tuning. So I won't try to rehash it. I used to tune them with a signal generator and a receiver....long ago!

There may be some other things in the hook-up making trouble for you.