AidanLunn wrote:Thank you, I wasn't sure whether it would have to have a partcular diode as it's printed on the (Ferguson) schematic - that suggested to me that only that type or equivalent would be suitable ...
AidanLunn wrote:After sitting on my "round tu'it" pile for a while, I thought I'd tackle what should be an easy fix whilst parts for my two TV projects come through.
This VCR had no life in any lights on the front panel, bar the VU meters, wouldn't reproduce anything at all from the standard audio stack and there was not a peep of any life on the SCART video input - output is fine. Otherwise, the machine was fine.
On CN2 on the PSU board:
Pin 2: -30V DC (measured as 52V)
Pin3: 3.9V AC (measured as 15V)
Pin4: also 3.9V AC (measured as 1.2V)
pin6: 45V (52V)
I think I have routed this all down to diode D24 (o/c), which is type RD8.2EB2, unfortunately there are not any sites on Google that seem to sell these. What substitute would be suitable?
Ferguson version of this VCR is the FV33H (an example of which I also have in my collection).
AidanLunn wrote:D24 seemed to be short circuit. My OP had a typo, it was -52V. Replacing this fixed that back to -30V. Both 3.9V AC rails are still unequal, so that narrows it down to R22, a fusible resistor, or the couplers C29 and C30, which both read at 0.002uF.
AidanLunn wrote:Thank you R2B, measuring the AC rails correctly read out 15V.
Red to black wrote:Post up the voltages you have now on CN1, you can miss the AC ones off if you wish as you have confirmed they are present.
I will have a look at the display panel for you, although this will be for the Ferguson FV33-H and so may not match physically exactly, but the basic parts should still be present as that is how that display type has to work.
Also in the new post put up exactly what symptoms you now have, you can also post up any other voltages after the regulator. be aware that some of these are switched.
Symptoms (pre-fuses blown):
No display on the LCD panel, no LEDs lit on same panel, bar the VU meters, which flash for a second when the machine is switched on from standby.
No video input on SCART, output is OK
No audio from normal audio head stack
Only audio from HiFi soundtrack, downmixed to mono
Machine seems to obey all commands from both front panel and remote except the button to switch between mono/HiFi/mixed audio.
Seems a bit of a brain-buster!
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