[Amps] SB220 Meter blown

[donroden at hiwaay.net]

And back when the SB220 was built, meters were $3 each.

Today, if you want to protect the appearance and functionality
of your GG Amp's meters, I'd suggest adding an op-amp interface
to prevent high currents from damaging the movement.

Don W4DNR


Quoting Jim <jimw7ry at gmail.com>:

> WRONG.
>
> .6 or .7 or slightly more during an "event" volts is still enough to  
> blow up the meter.
>
>
> Thanks
> 73
> Jim W7RY
>
> On 5/15/2020 4:08 PM, Adrian wrote:
>> from ; http://www.somis.org/sb-220ci.html
>>
>> "6. Meter damage can be avoided by connecting two, ordinary = or  
>> >1A, any PIV, silicon rectifiers across the terminals on each  
>> meter. The two diode arrows should point in opposite directions."
>>
>>
>> On 16/5/20 1:10 am, Artek Manuals wrote:
>>> I am resurrecting a SB220 that had an apparent classic Grid/plate  
>>> short event. One of casualties appears to be the right hand meter  
>>> movement. This is the one for Grid Current and HV. I am pretty far  
>>> into it and the meter movement measures open , the internal shunt  
>>> resistor is blackened ( and open?)
>>>
>>> Anyone got a surplus movement from a parted out unit? Nothing  
>>> found on evil-bay at the moment
>>>
>>> Dave NR1DX
>>>
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