Assist with Spectra conversion

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n9wys
Posts: 102
Joined: Sun Apr 18, 2004 12:03 pm
What radios do you own?: Too many to list! :-)

Assist with Spectra conversion

Post by n9wys »

I have a 900 MHz Spectra that is giving me fits. I will apologize at the top of this message for its length, but other than break it down into multiple mesasages, I have no other way of posing my questions. I will explain what I have done so far with this radio, and then address my problems. BTW - I converted one other Spectra and had no problems - but then again, I didn't need to replace the Command Board in that one. (Please read on...) So here goes...

First off, I have performed the resistor mod to "stabilize/move" the VCO - it's working fine now. I use a 100k resistor, and all seems well.

I have also re-capped the unit (replaced the electrolytic caps with tantalum chip capacitors) that has gone OK - as far as I can tell.

This radio required the replacement of the Command Board due to severe damage which was the result of C460 blowing up and bruning deep into the board... a picture of the damage is in the photos area at the "AR902" yahoo group, and is available direct from me upon request.

I have been able to eliminate the FAIL 999 code by reprogramming the MLM and Command Board serial numbers to match. However, two problems still plague me:

1) I get ER 01/02 when I boot the radio. I have traced this to the trunked profile in the radio - when I select the only trunked Mode in the radio, I get the FAIL 002 code. I have tried to enter a new trunking profile and mode, using the information from the label inside the radio, and then deleting the "troublesome" profile; however, I still get ER 01/02 at boot, and FAIL 002 when I switch to the trunked mode. So something still is not correct there...

2) The control head is not opreating properly. I cannot select SCAN, DIR or anyting else. The only controls that appear to operate properly are VOL, MODE, HOME and DIM...and I'm not totally certain of that. If I select MODE DOWN past the first Mode (001 - where the trunked mode is stored) the display goes blank. It does NOT go to the last mode in the radio (I believe that is Mode 24 or something like that)... I have entered the Control Head TEST MODE via software and checked for the proper operation of the control head - when in the test mode, it shows that ALL buttons are operating properly. However, when I exit and return to normal operation, the buttons do not work again.

I have tried to look at the data stored in memory for both the Command Board and the MLM, but I get more confused as time goes on.

Here is what I currently see for these data bits:

Command Board data from address B681 - B690:
00 76 40 A3 19 FF F1 FF 64 85 90 1F 1F 20 00 00

MLM data at addresses from 6183 - 6192:
C2 8B EE 94 00 11 C2 8B EE 94 00 12 02 8B EE 94

I have checked all up and down in the addresses and cannot find where these two strings match - as reported on the Batlabs site.

My questions revolve around how I recover the rest of the operations of this radio... Is there a certain address that I need to bit-bang in order to "reset" the radio to see the control head properly again? And what do I need to do to eliminate the ER 01/02 / FAIL 002 codes? Of course, I can "stay away" from that Mode in the radio, and all is well - it transmits just fine on all the other conventional modes for repeater operation.

But I'd really like this to work properly altogether - and be able to select DIRect (talkaround) as well.

Can anyone give me some guidance on what I need to do, or where to check in the memory addresses to find out what is amiss? I don't want to keep plodding ahead on my own, for fear of turning this radio into a brick.

If you prefer to converse off list, I can be reached at
n9wys <at> ameritech (dot) net
Thanks in advance!
Mark - N9WYS
jmr061
was KB9KST
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Joined: Fri Sep 14, 2001 4:00 pm

Post by jmr061 »

The MLM and command board strings need to match. The MLM data looks like trunking but I didnt sit down and decipher it. The command strings looks like conventional data. What kind of radio did the command board come from?

I would take and make the MLM data match the command board for starters. You have the original values recorded so its no big deal switching it back if need be.

After changing the MLM string, read the radio and re-write it immediately to get rid of the fail 1/82. Do that and see if anything changes.

Jason
BDB
Posts: 281
Joined: Fri Feb 22, 2002 4:00 pm

Post by BDB »

I did several for some hams I bit banged the model number from a B2 to a C5 and they all worked great. I didn't try to add any other options - and I only got the radio to do 10 conventional personalities and 100 trunked but that beat 10 trunking only personalities.
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n9wys
Posts: 102
Joined: Sun Apr 18, 2004 12:03 pm
What radios do you own?: Too many to list! :-)

Post by n9wys »

I'm not sure now which radio I took the Command Board out of, or if it was a board that was sent to me for "testing"... I realize that they need to match data strings. I just want to make sure I enter it in the proper place - since I've read that they can be in address locations that are not necessarily "standard". So, should I enter the matching data string into the MLM in the "standard" addresses and try that??

Let me know whether the part number on the board itself would help in decyphering this.

Regarding changing the model to a C5 - if I can retain the amount of conventional modes in this radio, I'd prefer to do that - but if I have to wipe all the data and reload - resulting on only 10 conventional - I guess I can live with that...

Thanks!
Mark - N9WYS
jmr061
was KB9KST
Posts: 3176
Joined: Fri Sep 14, 2001 4:00 pm

Post by jmr061 »

Hit me up on AIM

Jason
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