Batboard

To start I have read the batlabs MSF interfacing info under the model specific site. I have also read (about 5x) kcbooboo white paper on it. Every time I read it I get more confused (to technical for me to understand)

Here is my issue. I have a CXB Uhf MSF with a zetron Model 38 controller interfaced and working very well.

I have acquired a Cat300DX controller and want to replace the 38.

I hooked up the CAT to the 38 wiring and it works (to a degree).

It sees COR, It recieves, It passes audio, and It keys the transmitter

BUT---It does not pass PL that is programmed into the SSCB. What spits out of the MSF is in csq, or the PL is being filtered by the controller.

SOOOO I am lost. I just don't understand the theory behind this style controller. The 38 generates its own TX PL, but the Cat doesn't. It needs either the radio or external pl board to do this.

MY QUESTION??? Any ideas on how to let the CAT controller control the repeater TX, RX, ID etc. etc. and use the MSF internal PL functions????

Thanks for any help with this....I am stumped with this thing. Rob

Assuming that your CXB station is equipped with TTRC [wireline control] and has current firmware, the interfacing is straightforward.

You simply program the MSF as a duplex base station [i.e. no internal repeat]. You program whatever receiver qualifiers you want [PL tone, etc.] and whatever transmit PL you want.

The program the I/O on the station option connector so that you have a receiver activity indication as an output and line PTT as an input. Then all you have to do to interface the CAT is connect those signals plus ground as well as the 600 ohm wireline receive and transmit audio and your are done.

XMO,
I don't know if I have the ttrc, where does this module or board live.

Also, Would interfacing to the MRTI connector work, or just the TTRC.

Do you or anyone have a detailed connection diagram for this box and controller.

Thanks, Rob

Hi Rob,
Unless your really pressed for time to get your MSF on the air I would do some searching around on some of the auction sites and find yourself a manual for the station. Going at an MSF blind really opens yourself up to alot of grief.
Doug

I have a manual for a vhf version (same controller as the UHF).

I have to look through it to see what the TTRC is and if I have it. I just don't have the manual in front of me while typing this.

My question is more theory based.

I am well aware of the function of the zetron "community style" controller. And like I mentioned earlier my current 38 is interfaced and working very well.

I have not worked with just a plain controller, nor have I interfaced one. I just don't understand how to achieve where the PL passes through or is made by the factory controller and the CAT allows other functions.

I interfaced the cat using my zetron connections, and all works except for the passing of the PL.

I am going to try reprogramming the box as xmo stated and still use my valid zetron connections.

If anyone has any further specific info on the cat or "NON PL" controller interfacing to the CXB msf it would help me greatly..

Thanks a million, Rob

My two bits worth:
I have no experience with the CAT300DX controller.
I found the manufacturer's web site, but they don't tell me very much.
I can tell you one thing, that is that the PL generated on the SSCB in no way is processed by the controller.

Try to remove the PL (CTCSS) input, (the wire from the controller, which may be loading the tone encoder) and set the RSS for your PL code.
There is always the possibility some one has cut the PL encode path.
I don't see why the PL function should not work.

This controller does not have 600Z I/O, so you must wire directly to the SSCB.
I have not used the MRTI connector, since all of the MSF that I have modified for Zetron 38, or Trident Raider have been on analog stations.

Normally, the PTT should go to the front terminal of the test PTT switch.
Zetron instructions has the PTT connected to local PTT which mutes speaker audio, which would mute the local speaker when the controller is in PTT mode.

This will also mute the PL so you MUST use local PTT.(TP9 pin)

The reason the test switch mutes PL is that for setting frequency, or level setting it is convienent to mute any signalling.

Please ask if I have not been clear enough.

Bernie has a good point. Someone could have surgically altered the MSF so it can't encode PL.

I would rip out all the interfacing that was done to the Zetron, then program and if necessary repair the MSF to where it can encode PL on its own.

Then just interface the CAT to the wireline and aux connectors on the side of the station. CAT controllers are easy to interface. The RX audio input is hi-z and can be driven by just about anything - even speaker audio. The 600 ohm MSF wireline will happily drive it.

The CAT transmit audio comes from an op amp through a 600 ohm resistor and a 10 uf cap so it is about 600 ohm and will be perfectly happy driving the MSF wireline.

Then just wire a ground, COR, and PTT to the aux connector, set the levels and you are done.

There just is no sense kluging a premium radio with make do hook ups to various points on the circuit board when everything you need was designed right into the product.

I have all of the connections done right to the circuit board as the original zetron installation instructions said. It works great.

I should add that the box is programmed for PL operation and does function when the 38 is unplugged.

I think I might have found what is going on.

The 38 instructions say to disable the pl via the front switch as well as the accdisable switch on.

This allows the 38 to cleanly generate its own pl's.....There is the problem.

I would have to imagine that I would need to program the repeater for base operation with pl. That way I do not have to mess with the PL and/or accdis switches.

I think that may work. The repeater should encode/decode the pl on board the sscb and by it beinf programmed as a duplex base it should allow the cat to control tx/rx and pass audio.

Ill try it and let all know. Rob

You are right... Program the MSF chip as a base station and PL encode and decode. The MSF will need to encode and decode PL since your controller won't.

TP9 for PTT - TP6 for COS - U829 pin 14 PL indicate - U834 pin 13 for TX audio injection - TP5 for unsquelched RX audio. Diode isolation might be needed COS and PL indicate.

There are other ways to interface... this is what I used.

Okay,
After four hours of screwing with this stupid thing I have given up.
I got the controller and repeater to work. It passed PL through the controller, but for some reason the voice and courtsey beeps are being broadcast out of PL, which is not what I want. I can't get this thing to work right.

So unless anyone has any ideas on allowing the beep and voice to go over with PL please let me know,

Otherwise it's the model 38 or bust......

Errrrrr....Thanks, Rob

Your TX audio injection point might be causing the courtesy tone to be transmitted without PL. If you want PL with the courtesy tone, try injecting your audio at U834 pin 13 and add a 1/4 watt 33K ohm resistor.
Doug

Doug,

I have TX Audio injected at U814 pin 2 via a 33k resistor.

I assume that you mean the tx audion injection.

What is the difference in the two injection points...I will try it later tonight and see what happens.

Thanks, Rob

Thats make sure we are on the same page... I have an Analog MSF and U834 is the "TX Audio Summing AMP" and pin 14 is the output pin of the Audio AMP but before the Splatter Filter. PL is present at this point in the circuit so that is where I injected audio.

I have a CLB Analog station and that, I believe, is where the confussion lies. I don't have a CXB manual but look at yours and see if you find the "TX audio AMP". Also, look at the Audio Routing Schematics and trace out the TX Audio line. You maybe able to inject around the "Local Audio" and or "Alarm Audio" stages.

Probe around with a service monitor audio probe while keyed and look for the sine wave of PL around the audio circuits. Does it have a pot for adjusting TX or IDC audio from the front panel? Inject there perhaps?

I should get a CXB manual as I have had to work on one before.
But, it was a RX sensitivity problem that I didn't need a manual for.

Doug.

Doug,
Okay, I was wondering what was up. I do have a cxb model which is a little different than wiring up a clb model...I will check around. Thanks, Rob