MT1000 Railroad Freq Problem

[Balki]

Hi Ya'll,

I have a VHF MT1000 16 channel radio that I purchased for Railroad listening, etc. The bandsplit is 146.0 - 174.0! Since most railroad freq's are on the 160.xxx area one would think that I should be able to be able to program them in with this bandsplit.

BUT

When I program say, 160.860 into a channel and load it to the radio that channel no longer works, and the radio won't even power up on that channel. Other channels work fine! Go back to old freq channel works fine. I have programmed one freq in 161.070 and that one works just fine, but anything in the 160's don't work.

Freq's I'd like to get in are:
160.860
160.980
160.990
160.800
160.770

If I program those in now then those channels become dead. I'm just settin here scratchin my head. (No Not Cooties!)

Any help would be appreciated.

BTW ... I am using RSS version R03.01.02 and I boot the computer to DOS with a DOS Start-up disk then run the MT1000.exe.
That's the only way I can access the serial bus. It won't work from Windows.

Thanks,

Balki

[Tom in D.C.]

BTW ... I am using RSS version R03.01.02 and I boot the computer to DOS with a DOS Start-up disk then run the MT1000.exe.
That's the only way I can access the serial bus. It won't work from Windows.


Motorola DOS programming setups don't work through Windows. There is a ton
of information on this exact subject available via a Board search. Only the newer CPS
programs are meant for Windows platforms. We all run DOS 6.22 when the older
RSS is needed, by a partition, or a separate computer, or the way you're doing it.

[k2hz]

Are you sure the radio is really 146-174 bandsplit and you have selected the correct bandsplit in the RSS??

I had identical symptoms with a radio that really was 146-174 hardware but someone had forced a
146-162 codeplug to convert the radio from 8 to 16 channels. It would not RX between 159.9-161
or TX between 160.7-162.0 But, RX would work again above 161 and on the WX channels.

In the 160-161 range the RX would either give an "out of lock tone" or motorboat.

Once I verified what the hardware really was by checking the RF board I resolved the problem by
reprogramming with a correct bandsplit code plug.

[Balki]

Are you sure the radio is really 146-174 bandsplit and you have selected the correct bandsplit in the RSS??

I had identical symptoms with a radio that really was 146-174 hardware but someone had forced a
146-162 codeplug to convert the radio from 8 to 16 channels. It would not RX between 159.9-161
or TX between 160.7-162.0 But, RX would work again above 161 and on the WX channels.

In the 160-161 range the RX would either give an "out of lock tone" or motorboat.

Once I verified what the hardware really was by checking the RF board I resolved the problem by
reprogramming with a correct bandsplit code plug.

Hi,
Thanks for replying! According to the RSS the bandsplit is 146-174 .... I don't know if that helps, but that's what it says.

The numbers on the RF Board read as follows:

NUD15328
NUD67728

Thanks Again,

Dave

[k2hz]

The NUD6772B is a 146-162 board. Your radio apparently has been programmed with a wrong code plug if it shows 146-174 when you read it. A 146-174 board is NUD7030.

You can try to reprogram by selecting the proper bandsplit and realign the radio or you may need
to get the proper codeplug.

The issue is that the VCO requies a negative bias that controls the frequency range within the board's bandsplit.

A 146-162 board requires -6 v bias for 155.35-159.85 RX and 155.20-160.700 TX and
-8V for 159.85-162.0 RX 160.70-162.0 TX

A 146-174 board is -4v for 153-161 RX and TX and -6V for 161-169 RX and TX.

The mismatch between what the board requires and what the wrong radio code plug is calling for on 160 MHz frequencies is what causes the symptoms you have.

[Balki]

The NUD6772B is a 146-162 board. Your radio apparently has been programmed with a wrong code plug if it shows 146-174 when you read it. A 146-174 board is NUD7030.

You can try to reprogram by selecting the proper bandsplit and realign the radio or you may need
to get the proper codeplug.

The issue is that the VCO requies a negative bias that controls the frequency range within the board's bandsplit.

A 146-162 board requires -6 v bias for 155.35-159.85 RX and 155.20-160.700 TX and
-8V for 159.85-162.0 RX 160.70-162.0 TX

A 146-174 board is -4v for 153-161 RX and TX and -6V for 161-169 RX and TX.

The mismatch between what the board requires and what the wrong radio code plug is calling for on 160 MHz frequencies is what causes the symptoms you have.

Thanks for the info I'll try changing the bandsplit and see if that works. I'll let ya know!!

Dave

[Balki]

The NUD6772B is a 146-162 board. Your radio apparently has been programmed with a wrong code plug if it shows 146-174 when you read it. A 146-174 board is NUD7030.

You can try to reprogram by selecting the proper bandsplit and realign the radio or you may need
to get the proper codeplug.

The issue is that the VCO requies a negative bias that controls the frequency range within the board's bandsplit.

A 146-162 board requires -6 v bias for 155.35-159.85 RX and 155.20-160.700 TX and
-8V for 159.85-162.0 RX 160.70-162.0 TX

A 146-174 board is -4v for 153-161 RX and TX and -6V for 161-169 RX and TX.

The mismatch between what the board requires and what the wrong radio code plug is calling for on 160 MHz frequencies is what causes the symptoms you have.

Okay I tried changing the bandsplit to 146-162 Mhz. and it took the frequency's. The channels worked, and I tried transmitting with my scanner locked on my RR Frequency's, and it keyed up on ALL the channels. Now I am going to set them as receive only. I think it works, but I won't REALLY know till I get close enough to pick them up. In any case thanks for the help. I'll let ya know!

Thanks Again,

Dave

[k2hz]

You should be OK if you use it for RX only. The TX deviation settings get messed up when the bandsplit is changed and you need to go through the RSS service adjustments. The RX should not be affected unless whoever programmed the wrong bandsplit also tampered with the adjusments on the RF board to try to extend the range.