HT 600 UHF out of band Programming issue...

[LZ1CBK]

Hi guys,

some days ago a friend of mine gave me one of those old genesis Motorola radios- HT 600 .
He knows I like this staff , so now I have a new toy in my collection . The radio is UHF band, 99 channels.
Bandsplit is 438-470 MHz, I believe just wonderful for HAM band.
What problem I face with it, is that I can't program out of band frequencies on it . The RSS doesn't accept frequencies under 438,000 MHz . I had some " talk" to it, and 438,000 is now 430,000 , but still the same problem . strange staff. The version I talk about is r03.01.00 , RSS for MT1000 .It supports 99 channels.
other versions I have are : r02.03.02 & r02.01.00 , RSS for HT 600 ,they accept any frequency within the HAM range 430-440 ,without problem, just warning about, but the number of channels are only 6 , I don't see any option of adding channels on this versions.

Just wondering where I might be wrong ?? I never play before with HT600 . But wish to use this radio for HAM, as it looks very reliable and strong.
Would appreciate your help.

Cheers,

Boris

 

[b7spectra]

Try holding down your shift key while typing in the frequencies:

437.950 would look like $#&.(%) (don't hold the shift down on the decimal)

 

[LZ1CBK]

Try holding down your shift key while typing in the frequencies:

437.950 would look like $#&.(%) (don't hold the shift down on the decimal)

I will try this and will report

 

[LZ1CBK]

Try holding down your shift key while typing in the frequencies:

437.950 would look like $#&.(%) (don't hold the shift down on the decimal)

Unfortunately this trick doesn't work.
However, I manage to read /write the radio only with the MT1000 RSS .The RSS for HT600 I have, doesn't accept the RIB ( I get such alarm from it) . The PC I use is dedicated specially for /\/\ -PII-300 MHz , I run the RSS under DOS.

 

[62Truck]

The radio you described in your first post is a MT1000. The HT600's are either 2 or 6 channels. The MT1000's come in 8,16,32 and 99. You would need to use the MT1000 RSS. As for programming out of band on the MT1000's you need to do a little hex editing with the software that info can be found at this link... HT600/MT1000

Its fairly easy to hex edit for these models I have done with with some VHF versions that were 152.9-174 split to bring them down to 146 but the VCO didn't like it.

And before someone says there is no 152.9-174 split MT1000, there is I had 4 of them and they were ex NPS radios

 

[62Truck]

I just noticed your location. The radio you have is a HT600 or HT600E? If its working with the MT1000 Rss I would suspect that it is a MT1000

 

[LZ1CBK]

I just noticed your location. The radio you have is a HT600 or HT600E? If its working with the MT1000 Rss I would suspect that it is a MT1000

My radio might be HT600E, as per the attached from somebody not original face label...
No labels on the back of the radio . According the engravements and the battery replaced ( Alexander )
I suppose the radio is from USA, not from Europe .
Aniway, I will save a codeplug with 99 channels, and will try to HEX edit the codeplug , but 198 frequencies will be not a simple task to change :-(
I hoped that HEX editing the RSS itself may do my life easier . I swapped 438000000 with 430000000, and the new bandsplit appears in the main bandsplit menu ( F5) , but after entering frequencies below 438 ,000 MHz, the RSS corrects them automatically . No other place I found ,where 438000000 to be swapped , maybe I am wrong somehow.
I will play now with the codeplug,and will report for the results.

 

[LZ1CBK]

Just HEX edit the codeplug, and program it back to the radio . Looks well, RX till 430,000 .
However under 437 MHz radio doesn't want to TX. Seems like PLL doesn't manage to lock, but I am not quite sure . Is the PLL so sharp edge ? Have some of you done modification of the PLL to TX on 431,000 ? I need this as I would like to use this radio on repeaters ( 439,xxx MHz ,-7,6 MHz)

 

[N4KVE]

Even if you can trick the radio to accept the frequencies, will it correctly work at the freq's you want? Years ago I had a mint MT1000 that was in the 438-470 band. Most of the year it worked just fine on the ham freq's. [440-450] But for 2 weeks every year, when the county fair came to town, I needed the radio to work in the 467 range. Even though the radio was spec'd for 438-470, & 467 was in that range, the radio didn't work very well at 467 while tuned for the ham band. I had to retune the radio to work well at 467, & when the fair left town, I retuned it back to the ham band. During this 2 week period, the radio worked well at 467, but suffered at 440-450. Finally, I had a friend who worked at the factory in Plantation do his best to tune the radio so it would work in the whole bandsplit. [438-470] While he did his best, it wouldn't work quite as well as specifically tuning the radio for 440-450, or 467. But I left it as he tuned it, & this way I didn't have to retune the radio twice a year. I put up with the slight loss of performance. My point is since you are trying to use the radio out of it's tuned bandsplit, will it even work to spec in the area you want it to work? Nowadays, a MTS2000, or HT1000, works equally well at 403, or 470, & even then to 478. Also, 450-512 versions seem to work just fine in the 440-450 split. Good luck. GARY N4KVE

 

[LZ1CBK]

Even if you can trick the radio to accept the frequencies, will it correctly work at the freq's you want? Years ago I had a mint MT1000 that was in the 438-470 band. Most of the year it worked just fine on the ham freq's. [440-450] But for 2 weeks every year, when the county fair came to town, I needed the radio to work in the 467 range. Even though the radio was spec'd for 438-470, & 467 was in that range, the radio didn't work very well at 467 while tuned for the ham band. I had to retune the radio to work well at 467, & when the fair left town, I retuned it back to the ham band. During this 2 week period, the radio worked well at 467, but suffered at 440-450. Finally, I had a friend who worked at the factory in Plantation do his best to tune the radio so it would work in the whole bandsplit. [438-470] While he did his best, it wouldn't work quite as well as specifically tuning the radio for 440-450, or 467. But I left it as he tuned it, & this way I didn't have to retune the radio twice a year. I put up with the slight loss of performance. My point is since you are trying to use the radio out of it's tuned bandsplit, will it even work to spec in the area you want it to work? Nowadays, a MTS2000, or HT1000, works equally well at 403, or 470, & even then to 478. Also, 450-512 versions seem to work just fine in the 440-450 split. Good luck. GARY N4KVE

Yes Gary,

I fully agree with you . I also have several Motorola Spectra & Saber, which work out of band quite well .
I mean 440-470 bandsplit dedicated radio works fine in the range 430-440 MHz ( this is all what we have in Europe in 70 cm band ) . But they are much later generation of equipment release.
However, the MT1000, though it is much older generation equipment, I can easy see that the radio parameters and quality of this model are really wonderful , especially for its age. So I will use it in the range 438-470 and will not complain .
Actually it RX very well till 430,000 MHz . The issue with PLL appears to be for TX .