Information about the ASTEC UM1286 Modulator

Hardware Hacking, Programming and Game Solutions/Cheats
Post Reply
Alastair
Posts: 669
Joined: Fri Jul 18, 2008 11:33 pm

Information about the ASTEC UM1286 Modulator

Post by Alastair »

I've been trying to find out information about the UM1286 modulator, specifically what each screw adjusts. Today I have finally found that information hidden inside the service manual for the Memotech MTX 500/512, no wonder it took me so long to find!

The manual can be found at http://www.primrosebank.net/computers/m ... anuals.htm - be sure to download 'MTX 500/512 Service Manual and Technical Information (5MB)' and not the larger size download. The relevant details, including how best to test and set the modulator, can be found on pages 42 and 43.

Does anyone know what 'cable compensators' do?
sixxie
Posts: 1346
Joined: Fri Jul 18, 2008 8:36 am
Location: Hertfordshire
Contact:

Re: Information about the ASTEC UM1286 Modulator

Post by sixxie »

Alastair wrote:Does anyone know what 'cable compensators' do?
I think they might compensate for the ca... No, I have no idea :)

Maybe something to do with matching impedance of the co-ax?
User avatar
robcfg
Posts: 1529
Joined: Sat Apr 04, 2009 10:16 pm
Location: Stockholm, Sweden
Contact:

Re: Information about the ASTEC UM1286 Modulator

Post by robcfg »

The funniest thing is I did that pdf version of the MTX 500/512 Service Manual and Technical Information!

I got the manual from a friend and reconstructed as close as possible to the original, including damaged illustrations.

I never thought it would be useful here years later... :mrgreen:
Alastair
Posts: 669
Joined: Fri Jul 18, 2008 11:33 pm

Re: Information about the ASTEC UM1286 Modulator

Post by Alastair »

robcfg wrote:The funniest thing is I did that pdf version of the MTX 500/512 Service Manual and Technical Information!
Wow, it's a small world. Either that or you Rob are a colossus in the world of retro computing.
User avatar
robcfg
Posts: 1529
Joined: Sat Apr 04, 2009 10:16 pm
Location: Stockholm, Sweden
Contact:

Re: Information about the ASTEC UM1286 Modulator

Post by robcfg »

Thanks for the compliment!

It is indeed a small world. It's true that I've done a lot of preservation stuff too but nowhere near some people I know.

Always glad to help! :mrgreen:
Post Reply