[ARC5] Fw: Receiver current drain

[Bob Macklin]

If you don't want to use a headset why not just use a small audio amp 
driving a Speaker.

When I was using these receivers in the late 50'a I was always using a 
headset.

It seems to me that the section of 40M between 7200 and 7300 would be a good 
place to play with Command Sets on AM. Here it seems like a wasteland.

Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message ----- 
From: "J. Forster" <jfor at quik.com>
To: "Neil" <neilb at ihug.co.nz>
Cc: <arc5 at mailman.qth.net>
Sent: Thursday, January 06, 2011 8:42 PM
Subject: Re: [ARC5] Fw: Receiver current drain


> Yes, but in my view ripping out the original transformer is a poor idea.
> I'd use an external line to VC transformer to step the Rx output down to
> the speaker.
>
> -John
>
> ===============
>
>
>>> I'm not so sure lowering the cathode resistor is such a good idea.
>>>
>>> The suggested change will roughly double the 12A6 plate current, and
>>> hence
>>> increase the dissipation in the output transformer primary by 4X.
>>>
>>> It also might saturate the transformer with excessive DC, since the
>>> radio
>>> has a single ended output stage.
>>>
>>> Best,
>>>
>>> -John
>>
>>
>> Good points, except that the original output transformer is totally
>> unsuitable for loudspeaker operation and virtually all modified
>> sets have had a normal 5K - 4 ohm transformer fitted anyway,
>> which are rated for the conditions you mention.
>>
>> 73 de Neil ZL1ANM
>>
>> ______________________________________________________________
>> 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: http://www.qsl.net/donate.html
>>
>>
>
>
> ______________________________________________________________
> 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: http://www.qsl.net/donate.html
>