Thread: Sinclair mtv1
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Old 11-09-2017, 04:56 AM
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timmy timmy is offline
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Quote:
Originally Posted by jr_tech View Post
For grins, I took the cover off of the VHF tuner... YIKES! brain surgery is correct! Here is what mine looks like:



I have identified the 4 varactor tuning diodes and painted the tops with red paint... the 5 band switching PIN diodes were factory painted yellow (#5 is barely visible under coil next to blue and red top semiconductors)... the RF transistor (barely visible under tan wire and coil) was factory painted white and the oscillator and mixer transistors are painted blue on the tops. Do we agree?

jr
yes it looks right although I did see the other diodes and didn't know what they were but you had said there were varactors and pin diodes so what I took out may have been good and it could have even one of the transistors. The tan wire on mine was green corroded and making no contact so I fixed it but made no difference , befor I lost brightness. Well I'll tell you if someone knew these little sets and told me things to change and it would be successful I would probably do it since the only thing I know is the tuner is dead but the brightness problem if it didn't damage the IC next to the line amp pot then it's more likely a ksp44 transistor not a problem but the IC , there is no info on that to change it.

Last edited by timmy; 11-09-2017 at 05:22 AM.
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