Spectra channel capacity question

[Jim202]

I have been using and playing around with the old work horse called Spectra for a long time. Just recently it came to my attention that not all of the Spectra radios would do the full 128 channels. They stop at 99 channels.

Does anyone have any feedback on why some radios will do the 128 and others will only do the 99 channels? Have looked at the MLM versions and it doesn't seem to follow the radios with the lower channels. My guess is there is something on the control board limiting the channel count. Unless there is a software location that no one has stumbled across yet in the bit bang section.

By the way, for those that will ask, I am using the series 9000 control heads. Some call them a W9 head. The same head works just fine on a 128 channel radio.

Jim

[KE7JFF]

The Motorcycle Spectra I have does 128 I know....

[kcbooboo]

The Hand-Held Control Head (HHCH or A3) only has two digits for the channel display, so it will limit you to 99 channels. All the other heads have VFD displays and will allow more channels plus alpha-numeric names.

Bob M.

[Bill_G]

Just for s&g's I'll have to see if a d44kma will go to 128 channels or not. Thankfully, none of my customers ever had me attempt to fill every channel in their radios.

[Jim202]

Hi bill, have had a few comments both on and off the board here on this.

One of the comments was about the government dual band package using VHF and UHF with the SIU, the security package on both radios and the siren group. Been there done that with the W3 HHCH. Got tired of all the clutter and made some mods to get rid of the security boxes and made a cable to bypass them.

The next issue that came up was the fact that the SIU has had a history of failing to power up the radios. This was found to be a problem with one of the voltage comparator circuits that caused the micro to not finish going through the power up sequence. Found that cutting one pin off the micro solved this problem.

Next got tired of the SIU and the HHCH. Made the next step and pulled all that out and started using the W9 or 9000 heads as some call it. This was when I started using all 128 channels. Have a good number of the T83GXA series radios all running the 128 channels. The radio in question is a T84GXA series radio.

One of my friends up in New Hampshire has gone through a larger number of these radios than I have. His statement is that the MLM version number does not seem to effect the channel limit. He has seen a few radios that just won't go above the 99 channel limit.

Jim

Just for s&g's I'll have to see if a d44kma will go to 128 channels or not. Thankfully, none of my customers ever had me attempt to fill every channel in their radios.

[Will]

The MLM in the HHCH radios is different than the A4, A5,A7 or A9 MLM with some parts missing. They usually have a low version number.

All the non HHCH Spectras have the 128 channel capacity except trunking models.

[Jim202]

The MLM in the HHCH radios is different than the A4, A5,A7 or A9 MLM with some parts missing. They usually have a low version number.

All the non HHCH Spectras have the 128 channel capacity except trunking models.

I am wondering if in the cases of the radios I converted from the HHCH original to the W9 head operation, if the code plug I forced into the radio for zone operation made the difference. They were all VHF T83GXA version radios.

Guess I will have to look around for a UHF code plug that has zone operation. Anyone have a codeplug that will fit into a T84GXA that has zones that I can try?

Jim

[motorola_otaku]

I am wondering if in the cases of the radios I converted from the HHCH original to the W9 head operation, if the code plug I forced into the radio for zone operation made the difference. They were all VHF T83GXA version radios.

Were they originally A3 or A9 radios? Only factory A3 radios had the "reduced" MLM boards with hard 99-channel limits.

[kd5ual]

see what you find at mlm location 6128
80 = 128
63 = 99
remember every feature enabled on the mlm has
to be enabled on the command board as well

[wa6jbd]

see what you find at mlm location 6128
80 = 128
63 = 99
remember every feature enabled on the mlm has
to be enabled on the command board as well

I have a couple of questions....

Is this one of the known moflag features? I can't see anything on the published moflag feature lists that this would correspond to.

Isn't that MLM location in the area that 'travels around', depending on the size of the codeplug? What would be the corresponding fixed location in the vicinity of B681?

[kd5ual]

I dont have a firm answer
the 6128 location was found by Bruce Lane while trying increase the number of modes above 128
if you look at the relationship of 6128 to the known mlm moflag location then look ahead of B681
by the same number of locations and see what you find that matches what you have at 6128
this is just a guess as i have not looked for it
you may also have to bitbang the model number from a3 to whatever control head you plan to use on both the
mlm and command board or install a new mlm board and reinitalise the command board and align

[Jim202]

I did the bit bang change at 6128 and it did change the channel limit to the 128 modes. This is a good detail to know.

To answer the other question that was asked, to my knowledge, this is not a moflag selection.

Jim

[RADIOMAN2002]

Now I wonder what would happen if you increased to say 160 modes? Does it do a wrap around like a Maxtrac when you go above 40 modes?

[Jim202]

Now I wonder what would happen if you increased to say 160 modes? Does it do a wrap around like a Maxtrac when you go above 40 modes?

I tried to day to raise the number beyond the 128. The software will take it, but when you try to program the modes, it comes up with a memory error that you have exceeded the memory available. Will play with it some more.

Jim

[RADIOMAN2002]

I have found that depending on the model number certain options eat up memory. You might try using an A-7 head instead of an A-9. You might get more available memory that way.