[ARC5] BC-454-B Power

[Al Klase]

Mike,

Don't be a wimp! *Read the Freakin' Schematic!*

Pull the tubes and make continuity measurement between the #2 and #7 
pins on the various sockets.  You're dealing with three series circuits 
in parallel.  Shouldn't take but 10 minutes to determine if it's in the 
original configuration.

Good luck,
Al


On 7/19/2021 9:51 AM, MICHAEL BITTNER wrote:
>
> Not wanting to poke around the underneath to trace the wiring, Instead 
> I measured the cold filament resistance of each tube (not exactly the 
> same for each one) and then did the math for all of these 12-Volt tube 
> filaments in parallel.  It came out to 2 Ohms down to 4 decimal places 
> as I had originally measured at the dynamotor terminals.   So this 
> puppy has either been converted for 12-Volt power (very workmanlike 
> job) or was originally built that way.  Was there ever a factory-built 
> 12-Volt version of the BC-464-B?  Mike, W6MAB
>
>> On July 19, 2021 at 1:58 AM Brian Clarke 
>> <brianclarke01 at optusnet.com.au> wrote:
>>
>> Not such a good idea, Ken.
>>
>> This idea of substituting 6 V tubes really only works if all the 
>> heaters are in parallel. 6SK7, 6K8, 6SR7 all require 6.3 V @ 0.3 A. 
>> The 6V6 heater requires 0.45 A.
>>
>> Further, the 6V6 is not a good match for anode load; a far better 
>> match, and available in metal with the same pin-outs as the 12A6 and 
>> 6V6, is the 6F6, anode load 7 k Ohm , but heater current 0.7 A.
>>
>> 73 de Brian, VK2GCE
>>
>> *From:*arc5-bounces at mailman.qth.net 
>> [mailto:arc5-bounces at mailman.qth.net] *On Behalf Of *Kenneth G. Gordon
>> *Sent:* Monday, 19 July 2021 2:24 PM
>> *To:* 'MICHAEL BITTNER'; arc5 at mailman.qth.net; Robert P. Meadows
>> *Subject:* Re: [ARC5] BC-454-B Power
>>
>> On 18 Jul 2021 at 21:16, Robert P. Meadows wrote:
>>
>> > How about checking the wiring against a proper schematic. Then you will
>>
>> > know.  First check the tubes.  A quick change to 12v filaments is to 
>> install
>>
>> > 6 v filament tubes…   Not hard R
>>
>> Use a 6V6 in the 12A6 socket. Base diagrams are identical: 8AC
>>
>> Ken W7EKB
>>
>
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: https://www.qsl.net/donate.html

-- 
Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20210719/a592ef87/attachment-0001.html>