[ARC5] Powering an ARC-5 Receiver After Long Storage

[Brian Clarke]

That screen supply divider is the bulk of the current draw. There is
also the RF gain control circuit - 360 k in series with the RF gain
control, which could be anywhere between 0 and 50 k. This additional
drain could be, therefore between 0.6 and 0.7 mA.73 de Brian, VK2GCE.
On Wed, 21 May 2014 21:24:01 +1200, Neil responded:

 > In the past, I've powered radios in stages:
 >
 > First, applying filament only for several hours.
 >
 > Second, applying B+ only, in slow steps of about 20 V up to rated
B+.
 >
 > Third, applkying both Fil and B+ and checking operation.
 >
 > In the second stage, there is no current through the tubes. Does
anyone
 > have the nominal B+ current for the radios in the B+ ONLY states?
This is
 > basically a bypass cap leakage test.

 With only B+ applied, the two 7K divider resistors for the screen
grids are
 the only load, aren't they?

 So the drain = 250/14K = about 18mA.

 73 de Neil ZL1ANM

 On Wed, May 21, 2014 at 1:37 PM, J. Forster  wrote:

 > I have a couple of ARC-5 receivers that have been in storage for
unknown
 > years.
 >
 > In the past, I've powered radios in stages:
 >
 > First, applying filament only for several hours.
 >
 > Second, applying B+ only, in slow steps of about 20 V up to rated
B+.
 >
 > Third, applkying both Fil and B+ and checking operation.
 >
 > In the second stage, there is no current through the tubes. Does
anyone
 > have the nominal B+ current for the radios in the B+ ONLY states?
This is
 > basically a bypass cap leakage test.
 >
 > Thanks,
 >
 > -John

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