780 data slicer?

[BJ_NORTON]

I have heard that the 780 has an internal data slicer (which makes sense to decode control channels internally), that can be tapped like the discriminator and used to run trunker. Is this true? If it is I would like to try it and use it to run trunker. Has any body heard of this or actually done it?

Thanks BJ

 

[h8tdigitalradio]

Hello,

Here is a link for the info you are requesting. http://myweb.accessus.net/~090/bc-780xlt.html#disctap

HTH

73

Dave AKA The Tripzter :shock:

 

[EricCottrell]

Hello,

If you tap point 'A' then you can use LTRTrunk as well.

I noticed the 'B' point will work if the scanner is in Remote mode.

The 'A' point is at the output of a slicer circuit that has a non-filtered mode used for Motorola/Edacs control channels and a low-passed filter mode used to detect the Motorola end code and used for LTR. When I use trunker I scan a motorola bank first, usually holding on the control channel so it does not switch to a voice channel and change to low-pass mode. I scan a LTR bank to put it into Low-Pass mode. Once this is set you can do searches or scan a conventional bank and the scaner will stay in the filter mode.

73 Eric

 

[BJ_NORTON]

first, thanks for the quick replies-that was really quick-and I appreciate the help. I have another question or two.

according to this you can bring the Data out on a seperate RCA jack, like a discriminator, or you can pull it through the DB9.

slicer output could also be run to pin-6 (DSR) on the DB9 connector that is already attached to the main PC board - this would eliminate the 2nd RCA jack, and make radio control and slicer available through the same COM port and DB-9 interface cable. The slicer data signal should go to the computer's DB9 COM port either pin 6 (DSR) or pin 8 (CTS). Alternatively, if you don't use the cable for computer control, you can tie pins 6 & 8 together, so that the signal is present on both pins at all times.

The most eligant way seems to be to use the db9 on the back. Does that mean that pins 6&8 are unused, or that this can overide what they are being used for?

Have either of you actuallyt done this? I have been toying with T4Win, but it has some hicupps monitoring an EDACS system, so I am looking for another way around T4win. I am assuming that if I take the signal out from the serial connector that trunker will be able to figure out what pins the signal is coming in on right?

thanks again

 

[h8tdigitalradio]

Have either of you actuallyt done this?

Hello,

Yes, the discriminator tap works excellent, and the dataslicer tap was wired to Pin8 of the DB9 connector on the unit. Use a resistor as a buffer.

HTH

73

Dave AKA The Tripzter :shock: