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alitonto
 
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Default TV tunes all channels but not properly.

Teak TV ct-M687;HDTV Any advice please.
All channels can be somewhat tuned but none of them look good.
Picture is distorted/wavy and the sound cuts in and out for about 5
minutes from when TV is first turned on.

I have tested with a VCR and cannot receive stations from the RF but
this is confusing me: I switch the VCR to test and can get the 2
vertical white lines by tuning the TV to channel 3 (via RF) but cannot
receive anything.
However I do get perfect picture and sound via the scart connector.

So far I have resoldered etc.; I have B+ at 12.11v and various voltages
on other pins at the tuner but no reading on the IF pin.

I would appreciate any thoughts on narrowing down the problem.
Thanks
ALI

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b
 
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alitonto ha escrito:
Teak TV ct-M687;HDTV Any advice please.
All channels can be somewhat tuned but none of them look good.
Picture is distorted/wavy and the sound cuts in and out for about 5
minutes from when TV is first turned on.

I have tested with a VCR and cannot receive stations from the RF but
this is confusing me: I switch the VCR to test and can get the 2
vertical white lines by tuning the TV to channel 3 (via RF) but cannot
receive anything.
However I do get perfect picture and sound via the scart connector.

So far I have resoldered etc.; I have B+ at 12.11v and various voltages
on other pins at the tuner but no reading on the IF pin.

I would appreciate any thoughts on narrowing down the problem.
Thanks
ALI


sounds like you need to check the I.F. section for bad caps and/or the
aft may need a tweak.
B.

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alitonto
 
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Default

I am not sure how to check the IF section because I cannot get a
reading with my digital meter on the tuner's IF pin. Is it possible to
measure some DC volts there or only frequency can be measured?
I have checked and replaced marginal caps so far.
Ali.

b wrote:
alitonto ha escrito:
Teak TV ct-M687;HDTV Any advice please.
All channels can be somewhat tuned but none of them look good.
Picture is distorted/wavy and the sound cuts in and out for about 5
minutes from when TV is first turned on.

I have tested with a VCR and cannot receive stations from the RF but
this is confusing me: I switch the VCR to test and can get the 2
vertical white lines by tuning the TV to channel 3 (via RF) but cannot
receive anything.
However I do get perfect picture and sound via the scart connector.

So far I have resoldered etc.; I have B+ at 12.11v and various voltages
on other pins at the tuner but no reading on the IF pin.

I would appreciate any thoughts on narrowing down the problem.
Thanks
ALI


sounds like you need to check the I.F. section for bad caps and/or the
aft may need a tweak.
B.


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Tom MacIntyre
 
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Default

On 11 Jul 2005 16:54:35 -0700, "alitonto"
wrote:

I am not sure how to check the IF section because I cannot get a
reading with my digital meter on the tuner's IF pin. Is it possible to
measure some DC volts there or only frequency can be measured?
I have checked and replaced marginal caps so far.
Ali.

The 2 DC voltage checks I can think of are the AFT (* VDC or so, if
memory serves) and the B+ (33 VDC).

I've seen weak tuners that couldn't produce a good image for cable
signal levels, but a video game deck was okay. Perhaps the test signal
from your VCR is a stronger signal, and the tuner is marginal. As a
test (not a repair) try an RF amplifier.

Tom

b wrote:
alitonto ha escrito:
Teak TV ct-M687;HDTV Any advice please.
All channels can be somewhat tuned but none of them look good.
Picture is distorted/wavy and the sound cuts in and out for about 5
minutes from when TV is first turned on.

I have tested with a VCR and cannot receive stations from the RF but
this is confusing me: I switch the VCR to test and can get the 2
vertical white lines by tuning the TV to channel 3 (via RF) but cannot
receive anything.
However I do get perfect picture and sound via the scart connector.

So far I have resoldered etc.; I have B+ at 12.11v and various voltages
on other pins at the tuner but no reading on the IF pin.

I would appreciate any thoughts on narrowing down the problem.
Thanks
ALI


sounds like you need to check the I.F. section for bad caps and/or the
aft may need a tweak.
B.


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