[ARC5] RF ammeters / BC442-A ...

[Henry Frederick "Meils" Meiseles]

I have two type "ANTENNA RELAY UNIT BC-442A," of which one is functional.

Is the 1 - 10 scale arbitrary or is it  actual/real amperes of current?

10 A seems like a lot for rigs in the 25-40 watt output class but considering
how often RF ampere meters burn out because of short period mismatches,
this might well be an intentional protectional "overshoot." Were ammeter
units also used for higher power rigs? The ART-13 has an RF ammeter of 3A,
if I remember correctly, even though it could deliver considerably more
than a Command transmitter.

A quick comparison did show "1" when 1 A was read on a second
series connected RF ammeter.  -- I could rig it to my RF wattmeter but
at present cannot generate more than 100W RF out to the 50 ohm dummy
load --- which would only yield 1.41 A, anyway. 

I don't know if my -442A is reading out as it should but I do get about  1.5 A
at 100W out into 50 ohms, which is close to the theoretical value.

Since RF ammeter burnt out is a common problem, (I assume some on the list
will object to this claim). What about fusing them ?

(Yes, I can always run my TCS transmitter output through my 442-A, 
and maybe will do so.)

I have some ideas using a different principle for RF current out readings.


Henry, Cph.