[ARC5] SCR-183/-283 4-5 MC Coil on 75 MTRs

[Ian Wilson]

Tube Lore doesn't give any history although it mentions the SD838
as a variant. This was a Sylvania 'developmental type' - loktal, 25V
130mA heater.

73, ian K3IMW



On Wed, Jul 9, 2014 at 8:19 AM, Geoff <geoffrey at jeremy.mv.com> wrote:

> Ive heard it said that the 1626 is a souped up 6J5G with increased
> emission to get the gm up and a new plate structure.
>
> Any idea how long they run that way? One trick was to run a filament at
> higher voltage and not worry about short life in wartime. No, Im not saying
> they used a 6.3V filament but something under 12.6V that cost less and used
> less critical material.
>
> Carl
>
>
> ----- Original Message ----- From: "Ian Wilson" <ianmwilson73 at gmail.com>
> To: "AKLDGUY ." <neilb0627 at gmail.com>
> Cc: "ARC-5 List" <arc5 at mailman.qth.net>
> Sent: Wednesday, July 09, 2014 10:48 AM
>
> Subject: Re: [ARC5] SCR-183/-283 4-5 MC Coil on 75 MTRs
>
>
>  Note that the max plate dissipation is 5W, not 6.25W. The 6.25W
>> number appears in the RCA data sheet under typical conditions:
>> 6.25W plate input, 4W RF output. This means that the plate dissipation
>> is 2.25W, comfortably under the 5W limit.
>>
>> 73, ian K3IMW
>>
>>
>>
>> On Tue, Jul 8, 2014 at 4:59 AM, AKLDGUY . <neilb0627 at gmail.com> wrote:
>>
>>  > Look up the operating data and the plate characteristics for a 12J5. >
>>> Then
>>> do the calculations for Class C.
>>> >
>>> > 73 de Brian, VK2GCE.
>>>
>>> Thank you Brian.
>>>
>>> I think I can actually do better than that. I have the RCA Transmitting
>>> Tubes manual for 1956 (price one dollar!) and it lists the maximum CCS
>>> ratings for the 1626 when used as RF Power Amplifier and Oscillator -
>>> Class
>>> C.
>>>
>>> Unfortunately it doesn't give typical operating conditions, hence my
>>> questions about plate current and bias resistor.
>>>
>>> Max plate voltage, current, and dissipation are 250V, 25mA, and 6.25W. I
>>> think I could probably run it at 5W and get between 3 and 4 watts out of
>>> it.
>>>
>>> 73 de Neil ZL1ANM
>>>
>>>
>>> On Tue, Jul 8, 2014 at 7:14 PM, Brian Clarke <
>>> brianclarke01 at optusnet.com.au>
>>> wrote:
>>>
>>> > Hello Neil,
>>> >
>>> > Look up the operating data and the plate characteristics for a 12J5. >
>>> Then
>>> > do the calculations for Class C.
>>> >
>>> > 73 de Brian, VK2GCE.
>>> >
>>> > On: Tuesday, July 08, 2014 4:48 PM, You asked:
>>> >
>>> >
>>> >  Referring specifically to the BC-xx-230 model:
>>> >>
>>> >> How does one determine the setting for the roller inductor?
>>> >> Has anyone tried using the 1626 triode for VFO and PA?
>>> >> If so, what B+ and bias resistor did you use?
>>> >> What is the optimum 1626 PA plate current for CW?
>>> >>
>>> >> Any other useful hints?
>>> >>
>>> >> 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
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 2014.0.4716 / Virus Database: 3986/7823 - Release Date: 07/09/14
>>
>>
>