[R-390] R390-A big knob removal

[Barry]

Hi Sam,

The larger knobs have a clamp ring with a bristol-drive cap screw which is accessible from the hole in the side of the knob.  Loosen that clamp and the knob should pull right off.

Thanks,
Barry - N4BUQ

----- Original Message -----
> From: "Studiumtelecom S.Rocha" <battcharger at gmail.com>
> To: "R-390 Mailing List" <R-390 at mailman.qth.net>
> Sent: Sunday, October 24, 2021 1:03:39 PM
> Subject: [R-390] R390-A big knob removal

> Hi Friends,
> I got one r-390A Amelco I, serial #1596, would like to paint the knobs, but
> but how can I  take the big knobs out from the radio? I have the Bristol
> key for the smaller knobs.
> 
> I still did not switched it on, first I have  change  the C553 crystal
> killer. The radio is complete and was stored for many years.
> Thank you all for the answer and help!
> 73s
> Regards,
> Sam Rocha
> Py1dkw
> 
> 
> Em sáb, 23 de out de 2021 10:38, Jordan Arndt <Outposter30 at shaw.ca>
> escreveu:
> 
>> Hi group....
>>
>> The 1960 S-W 390A I'm working on has no Line Level meter and I'm looking
>> at
>> re-working a couple of the correct size and style of meters that I have on
>> hand to install as such.
>>
>> Has anyone determined whether the original meter had copper oxide
>> rectifiers
>> inside the meter..?
>>
>> Was it a single diode, a full-wave or a bridge rectifier...?  I've gone
>> through the archives and haven't found a definitive answer to that
>> question.
>>
>> One of the 390As I have has a substitute Line Level meter and a diode
>> bridge
>> external to the meter which works well enough for my purposes so I'd be
>> happy to copy that circuit until I can find an original Line Level meter.
>>
>> I've already installed a replacement Carrier meter with an LM741 op-amp
>> ckt.
>> driving a substitute meter which works very well.
>>
>> Any info will be greatly appreciated...
>>
>> 73...Jordan VE6ZT
>>
>> ______________________________________________________________
>> R-390 mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/r-390
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:R-390 at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
> R-390 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/r-390
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:R-390 at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html