MT1000 152-174 Split

[S_Holmes]

Have 10 or so MT1000's that I saved from being thrown out from my local RedCross Chapter, they were donated to us a few years ago from the NPS these radios are 152-174 split. I've did some research on trying to get them to program on the 2 meter ham band, on Repeater-Builder they gave a little help on how too but I'm still confused, I have VERY little hex editing skills. Only thing I have hex edited was the RSS for my Saber that is a 146-160 split that I edited for 144-160. I noticed with the MT1000 its some what different, was wondering if any one could give me the proper steps on how to accomplish what I am trying to do with these MT1000's and curious on how low the 152-174 split radios will go.

Thanks guys
Scott Holmes
KC2OBW

[Al]

Scott, have you looked here for the step-by-step procedure?
http://www.batlabs.com/ht6hack.html

[k2hz]

There is no "152-174" split for the MT1000.

Later models were 146-174 and earlier versions were 146-162 or 157-174.

The 146-174 or 146-162 versions work fine on 2M above 146 but will not go below 146.

The 157-174 version will not work on 2m.

If it is a Red Cross and not a former Federal Govt radio it is probably either 146-162 or 146-174. You will see the bandsplit when you read the radio in RSS. Do not try to change the bandsplit to other than what matches the board in the radio.

I had a weird problem with a 146-174 radio a ham tried to convert to 2M by programming it with a 146-162 code plug with 2M frequencies apparently thinking it would make it work better on 2M. It did odd things with either the RX or TX VCO going out of lock on certain frequencies because the VCO control voltages are different between the two versions of RF board. It took me a while to realize what was wrong and program it back to the proper bandsplit.

The Batlabs hex edit hack may work below 146. I have no experience with it. The RF board in a 157-174 split radio definitely will not go anywhere near the 2M band.

[impalass427]

For the lower bandsplit radio wont the "shift key" programming method work to go below 146mhz?

[MTS2000des]

There is no "152-174" split for the MT1000.

Later models were 146-174 and earlier versions were 146-162 or 157-174.

The 146-174 or 146-162 versions work fine on 2M above 146 but will not go below 146.

The 157-174 version will not work on 2m.

If it is a Red Cross and not a former Federal Govt radio it is probably either 146-162 or 146-174. You will see the bandsplit when you read the radio in RSS. Do not try to change the bandsplit to other than what matches the board in the radio.

I had a weird problem with a 146-174 radio a ham tried to convert to 2M by programming it with a 146-162 code plug with 2M frequencies apparently thinking it would make it work better on 2M. It did odd things with either the RX or TX VCO going out of lock on certain frequencies because the VCO control voltages are different between the two versions of RF board. It took me a while to realize what was wrong and program it back to the proper bandsplit.

The Batlabs hex edit hack may work below 146. I have no experience with it. The RF board in a 157-174 split radio definitely will not go anywhere near the 2M band.

Every wideband (146-174) MT1000 I've owned will drop to 144 just fine using either the shift key trick or editing the C/P. some VCO's start to come unlocked about 143 and make a whine, but 99 percent of the radios have rated power and RX sensitivity I've ever programmed, and this would be in the couple hundred (for the CAP about 10 years ago).

[S_Holmes]

I really hate to correct you but RSS is telling me that this is a 152.9-174 split radio. You might want to recheck the info that you have because under the bandsplit screen there are a few different band splits on the VHF version . I'm going to try and use the Hex Editor that batlabs recommended, I was using a different hex editor and I wasn't fully understanding it.

There is no "152-174" split for the MT1000.

Later models were 146-174 and earlier versions were 146-162 or 157-174.

The 146-174 or 146-162 versions work fine on 2M above 146 but will not go below 146.

The 157-174 version will not work on 2m.

If it is a Red Cross and not a former Federal Govt radio it is probably either 146-162 or 146-174. You will see the bandsplit when you read the radio in RSS. Do not try to change the bandsplit to other than what matches the board in the radio.

I had a weird problem with a 146-174 radio a ham tried to convert to 2M by programming it with a 146-162 code plug with 2M frequencies apparently thinking it would make it work better on 2M. It did odd things with either the RX or TX VCO going out of lock on certain frequencies because the VCO control voltages are different between the two versions of RF board. It took me a while to realize what was wrong and program it back to the proper bandsplit.

The Batlabs hex edit hack may work below 146. I have no experience with it. The RF board in a 157-174 split radio definitely will not go anywhere near the 2M band.

[k2hz]

I see that the RSS does list that bandsplit but I have never seen one and the MT1000 series service manual only lists 136-151, 146-162, 157-174 and 146-174 as valid bandsplits.

(see 68P81067C40-B Page 11 for the tables of VCO voltages vs frequency for the various bandsplits)

I believe the 157-174 can be made to work down to about 155 with some tinkering so the 152.9-174 might go down to about 150 but I think 2M is questionable if that is the actual bandsplit of the radio.

[S_Holmes]

I see that the RSS does list that bandsplit but I have never seen one and the MT1000 series service manual only lists 136-151, 146-162, 157-174 and 146-174 as valid bandsplits.

(see 68P81067C40-B Page 11 for the tables of VCO voltages vs frequency for the various bandsplits)

I believe the 157-174 can be made to work down to about 155 with some tinkering so the 152.9-174 might go down to about 150 but I think 2M is questionable if that is the actual bandsplit of the radio.

I have about 12 or so of these radios and they all came from NPS I have read two of them and they are definitely 152.9-174 split radios (I'll have to go through the rest).. I tried programing the radio for 146.970 rx and the VCO wouldn't lock. And the RSS would only allow me to type in 151 MHz as the lowest freq with out doing any kind of hex editing.

[k2hz]

I suspect they might be an early model before Motorola came out with the full 146-174 bandsplit version. It sounds like they may have attempted to stretch the spread of the early 157-174 split for users that needed both Federal Govt and civilian Public Safety in one radio.

I can't find a manual that covers it or even a catalog listing.

There would probably be both VCO lock and RF bandpass issues attempting to get it to go below 151 based on the way the other MT1000 versions behave. It seems like 2-3 MHz below the design frequency is all the RSS will allow and the hardware gets balky below that.

[S_Holmes]

Okay so I have checked all the MT1000's there are 12 of them, 5 of them are the 152.9-174 split, and the other 7 are the 146-174 split. So yes it may appear that the 152.9-174 split radios are earlier models but some of the are the same revision "AN" and they all have the same model number