23-12-2011, 08:11 AM
(22-12-2011, 05:57 PM)pwdrive Wrote: Hello Mike, I am not an expert on meters but the first thing I would check if not already done so would be it's FSD with its rated current passing through it or by temp. substitution with say an AVO.
I have a receiver with a similar concept insofar that it's meter can be switched to monitor the anode current of any of the valves in the receiver thus giving a go / no go emission reading test, it is however dependant on AGC/RF gain settings which are Off and Full respectively, as to wether or not a meter movement can loose say 30% sensitivity I am not sure enough to say, I have never had it happen but that is not to say that it can't, defective internal shunt etc.
Lawrence.
Hi lawrence ,
Sorry for the late reply I missed your post (busy day yesterday! ). I have checked the meter and it is consistently reading low on current ( standalone outside of the transceiver ) and I think it is due to one of the reasons I state in my reply to Al.
Last night I checked the movement and there are 2 torsional springs , one at the top pivot point of the meter needle shaft and one at the bottom. This is standard construction. The top torsional spring is not uniform in its coil, one side is "bunched ". The bottom spring is uniform in its coil. I also note that the needle shaft is slightly loose in it's top pivot point .
I will look further into it this morning.
This is one for the Horologists among the group I think.
Mike
