increasin audio bandwidth Micor receivers

[glaenzer]

Hello;

Has anyone here ever attempted to increased the low and high frequency limits and flatten out the audio response of a typical Micor receiver ?

say down to about 50-60 Hz and up to 4500-5000 ?

if so, what did you change to acheive this ?

Thanks to all

Gary

[Tom in D.C.]

If you were to pick off the audio signal prior to the audio amp you might
try running it through an equalizer and small audio outboard amplifier.
Bear in mind that the audio on almost all communications systems is
designed for 300-3000 (sometimes 2500) Hz response. Also, if you
somehow widen it to go below 300 Hz the CTCSS tone becomes really
loud and annoying.

[glaenzer]

If you were to pick off the audio signal prior to the audio amp you might
try running it through an equalizer and small audio outboard amplifier.
Bear in mind that the audio on almost all communications systems is
designed for 300-3000 (sometimes 2500) Hz response. Also, if you
somehow widen it to go below 300 Hz the CTCSS tone becomes really
loud and annoying.

no CTCSS worries, I'd like to use a Micor receiver (ala 'SpectraTac' chassis) as an extra Remote Pick-Up receiver for seldom-used-but-need-it-bad-when-we-need-it locations

I guess I need to get hold of one and run a freq response on the raw discriminator output and go from there

[Will]

What other cards are in the Spectra-Tac chassis. This is not as hard as a mobile or station to do wide audio.

[WB6NVH]

This is apparently what the "Discr. Ampl." module for the SpectraTAC does. Takes raw audio from the discriminator and processes it separately from the regular audio-sq module, without restriction. I just acquired a SpectraTAC receiver which has one of these. The modules are not listed in the manual and while they have a regular TRN- prefix model number, they were supplied in -SP version SpectraTAC receivers.

The original purpose of this module seems to have been for use with MDT's on 800 MHz systems, so that the receiver would pass data.

I posted an inquiry about this module a few weeks ago but nobody had a schematic or any application notes. The module is full of IC's and not trivial. I see eBay seller "J-Panik" in Florida has some for sale on his website, but at what seems a rather steep price to me.

[bernie]

My two bits worth:
The receiver module used in the Micor SpectraTac chassis is exactly the same as used in the mobile, and base/repeater.
For the maximum band width down to DC use the Discriminator output.

[mcx1000]

This is apparently what the "Discr. Ampl." module for the SpectraTAC does. Takes raw audio from the discriminator and processes it separately from the regular audio-sq module, without restriction. I just acquired a SpectraTAC receiver which has one of these. The modules are not listed in the manual and while they have a regular TRN- prefix model number, they were supplied in -SP version SpectraTAC receivers.

The original purpose of this module seems to have been for use with MDT's on 800 MHz systems, so that the receiver would pass data.

I posted an inquiry about this module a few weeks ago but nobody had a schematic or any application notes. The module is full of IC's and not trivial. I see eBay seller "J-Panik" in Florida has some for sale on his website, but at what seems a rather steep price to me.

Be careful when buying stuff from Panik, he can't or won't test the stuff he sells, or is selling bad gear. I have purchased a few things from him and many times the gear is non-functional.I have also bought fully functional gear. So, Caveat Emptor.

[Will]

Seems he already has the Spectra Tac receiver and the ST line driver module CAN be mod'ed to get better frequency response. No need to buy extra hardware.

I need to know what audio module you havce? Number?
And how the audio is sent on to?

[WB6NVH]

The module I was referring to is in addition to the standard audio/Sq module, is labeled "Discr. Ampl." and is a TRN 8673B. Not listed in the SpectraTAC manual I had. I had an earlier post asking exactly what it was but nobody was familiar with them.