Telestrat mono video output .. ;(

If you want to ask questions about how the machine works, peculiar details, the differences between models, here it is !
How to program the oric hardware (VIA, FDC, ...) is also welcome.
Post Reply
User avatar
ibisum
Squad Leader
Posts: 861
Joined: Fri Apr 03, 2009 8:56 am

Telestrat mono video output .. ;(

Post by ibisum » Sat Jun 08, 2013 2:08 pm

Well I just booted up my Telestrat and discovered that, in the few months since it was last booted, it is now monochrome output - i.e. no color channel. No amount of 'tweaking' the cable fixes it. And I've verified that my TV works (with another Atmos) so its not that .. hmm .. anyone know what I can check next?

Godzil
Squad Leader
Posts: 755
Joined: Sat May 21, 2011 7:21 pm
Location: Between UK and France
Contact:

Re: Telestrat mono video output .. ;(

Post by Godzil » Sat Jun 08, 2013 6:14 pm

As the ULA is responsible of the RGB output, did you try to swap it with another ? (It should be the same as the ATMOS one so.)

Or between the RVG plug and the ULA there is at least two chips a resistor array (RP2 on the oric) and if I read correctly a 74LS368 (IC22). If the Telestart have the UHF output, the PROM (IC23 on the oric) could interfere too.

User avatar
kenneth
Flying Officer
Posts: 179
Joined: Fri Nov 26, 2010 9:11 pm
Location: France PdD
Contact:

Re: Telestrat mono video output .. ;(

Post by kenneth » Sat Jun 08, 2013 6:30 pm

I don't have a Telestrat but I think that means the ula and the rgb amplifier work correctly but the level is the same for the signals.. maybe the ground pin disconnected in the PERITEL plug ?
Try differents colors with INK instruction (only unmixed colors like 1, 2, 4) to be sure that all RGB signals reach the TV. :wink:

User avatar
ibisum
Squad Leader
Posts: 861
Joined: Fri Apr 03, 2009 8:56 am

Re: Telestrat mono video output .. ;(

Post by ibisum » Sat Jun 08, 2013 6:50 pm

Yeah, well drats. I've had a big Oric afternoon. The Telestrat doesn't boot any more. :( I think I must blame my incessant rebooting/booting/switching of power supplies/configurations.

I do still have a working Atmos+microdrive, but I had been hoping to use TELE-ASS on the Telestrat. Oh well.

When I have the druthers, I'll have another go at fixing the Telestrat, but it looks like its time to start finding busted components and .. my Atmos is good enough for my needs now..

Thanks for the details about what I should be checking; next week or so I'll have a go at fixing it. In the meantime, I'm writing an Atmos disk image as I type..

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest