Shadowmeter ? - Printable Version
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+--- Thread: Shadowmeter ? (/showthread.php?tid=7030)
Shadowmeter ? - Jim Dutridge - 07-11-2013
How does one bypass a missing shadowmeter?
RE: Shadowmeter ? - BrendaAnnD - 07-11-2013
Every circuit I've seen with a shadow meter, the meter could be bypassed safely by simply connecting the wires together.
RE: Shadowmeter ? - Jim Dutridge - 07-11-2013
Well, that should be easy enough to do. I was thinking I had to add a resistor in place of the meter.
RE: Shadowmeter ? - Arran - 07-11-2013
Is the coil driving the shadow meter open on your set or is the shadow meter just not functional? I would think that there is some sort of voltage drop across the coil since it consists of hundreds of turns of wire.
Regards
Arran
RE: Shadowmeter ? - jerryhawthorne - 07-12-2013
Well, if we would listen to the OP, the meter is apparently missing. As I recall, there are two differing set ups on Philcos, one with the meter alone supplying B+ to the front end of the receiver and one where it did the same thing but with a resistor in parallel just in case the coil should open and the the front end will still get enough voltage to work. If yours is a receiver that did not have that bypass resistor, I agree with Brenda , should work just fine with a bypass wire or maybe a 1-2K resistor if the B+ looks a little high. If it had that resistor in parallel, you shouldn't need to do anything.
Again, I know nothing!
Jerry
RE: Shadowmeter ? - simplex1040 - 07-12-2013
Hundreds of turns try 4000 I just unwound one.
RE: Shadowmeter ? - Chuck Schwark - 07-12-2013
Surprised no one has seen my Service Tips Section?
Service Tips Section:
http://philcorepairbench.com/tips/svctips.htm
Shadow Meter Repairs:
http://philcorepairbench.com/tips/svctip01.htm
Chuck
RE: Shadowmeter ? - jerryhawthorne - 07-12-2013
Certainly I have used your information Chuck. It indicates that the resistance of the coil should be about 1.1K based on the number of feet of the wire and resistance per foot.
Jerry
RE: Shadowmeter ? - morzh - 07-12-2013
In my 18 the shadow meter was simply shorted.
Somehow I think it does not have a huge effect on functionality.
RE: Shadowmeter ? - Jim Dutridge - 07-12-2013
OOPS, replied to the wrong post .