Samsung VT-380 VCR Sound Output Problem

[Eric]

I need help on my Samsung VT-380 Hi-Fi VHS. Playback sound and video
are ok if I use RCA jacks to connect to tv, but when I use the tuner's
tv out connection to tv there is no sound but video is ok. I suspect
defect with the tuner but cannot find actual tuner model available as
replacement. Is it possible to fix the tuner (If I am correct in my
assumption)? I am quite comfortable in soldering and desoldering parts
but do not have osc. equipment to check parts status in depth. I saw a
chip (LA 7577) sticking out from the tuner and have this wild idea of
just replacing that chip. I browsed through the web that it's an IF
Signal Processor for TV/VTRs. That part might be easier to look for
and buy than the whole tuner box. Am I on the right track. I would
appreciate some help. Thanks.

 

[Mark D. Zacharias]

Since you have audio from the raw outputs at the rear - the tuner section
itself isn't your problem. Sounds like the RF modulator portion of the tuner
isn't getting the audio in there. You could try resoldering that portion of
the tuner - otherwise you might be out of luck, as the cost of the tuner may
be too high.

Mark Z.

 

[Patch]

I need help on my Samsung VT-380 Hi-Fi VHS. Playback sound and video
are ok if I use RCA jacks to connect to tv, but when I use the tuner's
tv out connection to tv there is no sound but video is ok. I suspect
defect with the tuner but cannot find actual tuner model available as
replacement. Is it possible to fix the tuner (If I am correct in my
assumption)? I am quite comfortable in soldering and desoldering parts
but do not have osc. equipment to check parts status in depth. I saw a
chip (LA 7577) sticking out from the tuner and have this wild idea of
just replacing that chip. I browsed through the web that it's an IF
Signal Processor for TV/VTRs. That part might be easier to look for
and buy than the whole tuner box. Am I on the right track. I would
appreciate some help. Thanks.

You're probably right about the tuner\rf modulator being bad. With a HI-FI
VCR, why would you want to use the RF output jack? (you can't get stereo
output with this jack) The cost to replace the tuner would be pretty high. I
would use the video\audio out jacks & not worry about it.

 

[Eric]

Thanks for the comments, and yes, I agree about not using the RF
output jack on playback, however, (I forgot to mention) I need the
tuner to record tv programs that I miss while I am at work. With my
current tuner problem I only record the video part of the program.
Actually I tried a neat trick by connecting my tv monitor-out to the
RCA input jacks of my VCR thereby being able to record tv programs
while using my tv's tuner, however this won't work on using the vcr's
program mode since the program mode will only let me choose tuner
channels as the source and not the rca inputs.

Anyway this vcr is probably 10 years old and already served me a good
many years. I am trying to figure out whether to buy a used one or a
new one. I wonder if they actually still sell basic vcr's nowadays.
What I usually see on store shelves lately are DVD/VCR combo units.
And for my purpose these combo units are way out of my budget.

Again, thanks for the comments.

Eric

 

[Eric]

I actually desoldered and took out the whole tuner box so I can show
it to stores when I look for replacements. Since I cannot find a
replacement I soldered it back on and still exhibits the same problem,
no audio just video. I'll try your suggestion and resolder the RF
modulator part of the tuner box.

Anyway I guess I might really be out of luck and the next best thing
is to buy an inexpensive vcr with program functions. I really needed
the tuner to work to record tv programs I miss while am at work.

Thanks

Eric