[R-390] Resistance Measurements and Trouble Shooting

[W. Li]

On Feb 1:  Jim Brannigan <jbrannig@optonline.net> wrote:
Subject: Re: [R-390] Resistance Measurements and Trouble Shooting

>A few things to keep in mind.  The charts in the manual are
representative of all the radios and >not unique to your particular
radio....The type of meter in use will affect the voltage readings.   <snip>

Jim is quite correct in his suggestion. Our units are different, but
they theoretically should be within 20% of the published
voltage/resistance measurements. Measuring these values are facilitated
by using 7- and 9-pin tube extenders (sometimes found at hamfests) and a
good quality long VTVM probe tip. If you also enter the published values
into your spreadsheet, anomalies are easy to spot. One operation that
must be done (but is oft forgotten) is to set all the panel controls
exactly as called out for in the manual, as they affect our measured
values. This exercise may sound tedious at first glance, but the effort
will pay off if and when our units act up or die on us. 

W. Li
Mercer Island, WA