snipped:
Alex Bird said:
I'm having a fiddly time lining up the tape path in a Sony
SLV-ER7UY(uk pal), it's good but I've just put new heads in and I want
it to be perfect ;o)
Where can I find the RF envelope test point?
And what bandwidth is this signal? I have only a 50kHz pc based scope
here.
Do you need a test tape to make use of this?
Is there an envelope for the hi-fi heads too?
Alex
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Alex Bird:
The RF envelope "test point" (it may not even be a identifiable test point
but just a place on board) will usually be on or near the head preamp
board..... and yes, since the HiFi audio heads also operate as a modulated
RF signal you will also be able to visualize the RF envelope of those heads.
There are other adjustments and checks that must be done to properly install
new heads. In order to produce a proper alignment and interchange, a
factory test and alignment tape is required and as far as you scope goes
..... it's low bandwidth and sensitivity is completely and utterly USELESS
for this kind of measurement.
You would be best advised to take your fine VCR to a service shop for proper
head alignment and interchange adjustment..... the money you spend at the
shop will be much less than purchasing an expensive alignment tape, special
head adjustment tools, head penetration gauges,tension gauges, a new
oscilloscope, technical training and procedure manuals, etc. This is a
fairly routine job for an experienced tech with the proper tools and test
equipment, electronics knowledge and repair experience...... for the
novice, you risk misalignment of the heads, poor interchange with other
VCRs, and possible damage to the expensive heads, the vcr, and your tapes.