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Hi Dave, I'm now driving the AV input of my TV through pin 12 of J2 and the picture is rock solid. I hand picked a resistor to move the pic down slightly (the top line was partly hidden). The Uk101 does not have a variable resistor R57 to do this and it's a little tricky to fit a variable in the con...

I've solved the video problem I was having -the bad pic on my larger TV. I'm now driving it from the video output, rather then through the modulator. I changed the cable connecting the video o/p to the TV and it made all the difference - bad cable was the problem ! Previously the video output was mi...

Forgot the most important bit
Tadaaa !!

Hmmm.....Difficult to get a good screen pic. Must study photography

D.

Ah! The good news :) I've replaced 6 Ram sockets (upper 6) Also replaced the 24 pin sockets for the ACIA, Monitor, and Basic ROMS. I installed 8 K and it works perfectly :) I removed the sockets by breaking the frame and lifting them off , leaving the pins to be desoldered individually. I did notice...

Hi Dave, Mike, Did you tweak the level pot as Dave suggested. Mine is set full clockwise. Ah ! The UK101 did not have the variable resistors for adjustment that the Challenger had (No R57,R58). It's working on my very small TV - so the sync problem is not an issue for the moment. With respect to the...

Hi Dave, I've done all the permutations/combinations with the ram chips - as you suggested. It's now consistent in the sense that no matter what chips I put into the 6K slots, I get instability and hanging and occasional refusals to reset. Any time I try to put more than 6K in , I gt a problem. The ...

Hi Dave, Still struggling with Ram chips. I only had 6K in and it was reliable. I got some new old 2114s from USA (via ebay). When Itry to get more than 6K installed , it hangs on the mem test. Sounded like an address decode problem ? Some more tests/experimentation needed. With 8K installed now it ...

I've repaired the case and it now provides a stable platform for the pcb again. Failed RAM was stopping boot up - now fixed. I removed the 12 point connector (J3) again and mounted it under the pcb. That way it allows access to the modulator. Boots up npw - just a quick test - many ram chips failed ...

Tonight I powered it up as a test, after all the cleaning out of cobwebs and dead bugs. Did it work ? Not on your life ! A screen of garbage - not even tuning in correctly. I'm using an old TV which auto-tunes. Will not lock on to ch36 ..... I checked all the clocks - all ok Ah! Memories of past pro...

Hi All, I've ordered the Molex parts from Mouser UK . In the meantime , for your amusement , I've put some images on my home page. :( http://www.iol.ie/~themahony/ - very much a work in progress ......... forgive the raggedness ........ You may even see me bullfighting in my younger days. :) DenisM