[TheList] Tait TM8200 (Chris Hoffmann)

Mon Sep 11 16:20:33 AEST 2017

Hi Chris,

I have a programmer and can do firmware upgrades - but it won't help your
volume problem.
Trust me, I have spent the last 12 months looking into this - including
raising tickets with Logic Wireless as I had two
TM8200 which were both remote head models and both had the annoying
'volume' issue.
I have even had a lot of support from a very experienced Tait tech who
works for one of their agents, and he couldn't offer any solution.

The issue I had, which sounds like what you're experiencing is that from
about 7 o'clock to about 9 o'clock, the volume control
does very little.
The mute opens so you have very low level audio, then from 9 to about 11
o'clock that level doesn't change at all.
At 11 o'clock it suddenly jumps up, but from there onwards around to full
volume it increases in a smooth, normal fashion.
Effectively you can't turn the volume down to a listenable level, it's
either too quiet or too loud.

I tried doing a firmware upgrade, and this didn't help the problem at all.
The other thing I tried was attaching the head directly to the radio,
eliminating the remote interface.
The weird thing is that it worked for one radio (the VHF) and the volume
operated normally as you'd expect.
However, it made no difference on the other radio (the UHF) - the problem
was still there.
Had it worked for both radios, I would have said the remote interfaces were
the problem.

The difficulty with this issue is that the volume is controlled digitally
from the head. Data is generated from the position of the volume pot and
sent back to the radio body to determine how much audio is produced. Not
being able to read that data left me unable to diagnose any further.
This of course is typical of manufacturers - let's take something that
works perfectly well (an analog volume control) and f*ck with it to
supposedly make it 'better' and in the process stuff the whole thing up.

The Tait tech I mentioned above sent me a Tech Bulletin which I thought may
have been the solution, but it only applies to certain revisions of remote
interface and neither of the ones I had were of that revision.
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