More and more often I find myself working after midnight just to
earn a crust. Frequently, I find my eyelids drooping and, once, I
woke myself by nodding off into a switch mode power supply! But now I
have the answer. I bought one of those "helping hands" contraptions -
you know - the one with a magnifying glass and two crocodile clips on
articulated arms. It's so useful. I fit each clip carefully to an
eyelid and peer through the magnifying glass with my chin resting on
a cup of strong coffee. It's painful but it keeps me awake!
(No, just joking really).
I've had numerous calls from professional installers who think
that I, a bench bound repair man, should be able to solve their
problems. Surprisingly, I often can!
Recently the same symptom has occurred repeatedly: a noise in the
background of Sky Premier movies or what ever thay call it this week!
The complaints also include "sparkly" pictures on channels such as
"UK Living", "Moviemax" and "Sky Sports".
The problem comes from the new Eutelsat satellite "W2" at 16 degrees
east of south which transmits up to 135 Watts per transponder! There
are at least three adjacent channels being transmitted at the same
frequencies as the Astra channels. "Nile TV" affects Sky Sports,
"ESC" affects "Movie Max" and "Egypt TV" affects "UK Living". The
answer is to ensure that the dish is not distorted and to get it
aligned accurately. The adjustment is *very* critical. A spectrum
analyser may be needed in some cases. Ho hum, and of course you will
have to charge the customer LOTS of money - unless you did the crappy
installation in the first place. If adjustment is not possible
because the dish is twisted or poor quality then the only answer is
to fit a new dish - possibly slightly larger to give a narrower beam
width. Another possibility is to try a different type of receiver,
since some seem better than others at rejecting this
type of interference.
Note that HOT BIRD 5 is also high power and is likely to cause
problems
with 10 degrees East.
Another form of interference comes from the ONdigital terrestrial
transmissions. The effect of these is to make the satellite pictures
very "grainy". The answer is to retune the satellite receiver UHF
output to a different channel.
When Wossname from up Church Street waddled into the workshop I
groaned. He always arrives just when I'm in the middle of a most
frustrating problem. On this occasion he had brought a Grundig
receiver.
"Nuffin wrong wiv it", he announced. "Jus' locked menus".
Now I haven't seen many of these GSR1 receivers so I'm not very
familiar with it. I searched through my notes and various Satellite
Repair manuals but couldn't find a reset code anywhere.
"OK", I said, "let's try the Internet". Wossname looked puzzled so I
told him to put the kettle on while I entered the search words into
"Sherlock" on my new Apple Mac G3 computer. It took about 30 seconds
to find the answer at the SatCure web site.
To unlock menus: Enter the lock menu and 'Reset PIN'. This sets the
PIN to 1515.
Wossname tiptoed back with a cup of tea in his hand.
"Where's mine?" I asked.
Nowadays I don't repair D2Mac decoders. The type of person that uses
these is often the type who doesn't want to spend any money! That,
plus the fact that I have to have a pirate smart card in order to
test them, forced me to "throw in the towel".
However, the lady who brought in an SRD650 didn't look like a typical
viewer of questionable films so I agreed to have a quick look - at
the receiver I mean!
She explained that it turned itself off occasionally. After a few
seconds she could turn it on again with the remote but it was
annoying.
I checked the power plug for bad connections. It's always sensible to
start with the obvious.
In the SRD510 I have also seen this fault occur because of a bad
low-voltage connector inside so I looked at the plug which connects
5v/12v/27v/13-17v to the main board.
After I cleaned the connections with "switch cleaner aerosol" it
seemed to work OK so I left it on test. It was still on next morning
so I reckon that my guess was correct.
Nokia receivers are either very scarce or very reliable as I seldom
get them for repair. As a result, I'm not very familiar with them.
The receiver that came in was giving only 17 volts to LNB. It would
not change polarisation by dropping to 13 volts. Luckily, the cause
was a simple to trace dry joint on LM317T regulator.
I've had lots of problems with "no decoding" on later Pace models
using PTV111, PTV110, PTV115 etc. Even after swapping every I.C. and
capacitor on the board I've had some which refused to work. However,
Pace inform me that there are two different PTV115 I.C.s in use:
A CMOS version PTV115 with a "C" or with bright white marking:
Fit links J301, J302 so clock pulses go to pin 18.
NMOS version made by Siemens with dark yellow marking:
Fit links J300, J303 so clock pulses go to pin 19.
The Power Supply could be heard to fire up but the vacuum fluorescent
display wouldn't light. There was no LNB voltage and no pictures or
audio (just "snow" and "hiss"). Occasionally, the screen showed some
sort of mistuned picture when the tuner module was warmed up with a
hairdryer.
I confess that this receiver sat on the bench for a couple of days
and I had sleepless nights because of it. The owner is a personal
friend (isn't it always the case with the tricky repairs!) and I
didn't want to let her down.
Eventually I found that the symptoms were caused by cracked tracks
near the tuner solder lug. Really, I should have known because this
same fault causes other Grundig receivers to be "stuck in
standby".
Don't you just hate it when the owner stresses the urgency of a
repair then adds that he doesn't want to pay very much! Usually,
under these circumstances, I offer a Service Exchange unit. However,
I didn't happen to have an MSS501-IP lying around the workshop so
that option was out!
I embarked on option number two:
"Go away"
"Pardon?"
"Go away. I'm not going to waste my time on someone who brings a 400
receiver but doesn't want to pay more than 25 for a good repair. If
you want it cheap, take it to a cowboy. There's a good one up Church
Street.
At this point, the old boy must have seen the light because he came
over all reasonable and slapped a fifty pound note on the
counter.
"Horizontal channels go off when it's hot", he stated. "If it costs
more than that, let me know. Discount for cash, mind!" He hopped into
his "Discovery" and roared off, leaving his business card on the
counter. A solicitor - oops!
Anyway, I didn't try to trace the actual cause of the fault because
fitting the reliability kit of Ultra-Low ESR capacitors, RELKIT 10,
cured it.