[Johnson] Re: Ranger keyer problem

[Mahlon Haunschild]

Sorry about that, list.  My mail file wrapped around to an old posting & 
I didn't notice it until it was too late.

regards,

m.

Mahlon Haunschild wrote:

> Phil,
>
> Just use 6L6GCs.  They are plentiful, require no circuit changes, and 
> exceed the old 1614 specs.
>
> The 1614 was a 6L6 selected for higher voltage.  It was made back in 
> the days before the tube manufacturers knew how to (or chose to) 
> design a 6L6 for higher voltage.  Eventually, of course, they did just 
> that, first with the 6L6GB, then the 7027A (though the 7027A is really 
> a somewhat different tube), and finally with the 6L6GC.
>
> regards,
>
> Mahlon - K4OQ
>
>> Message: 1
>> Date: Thu, 23 Oct 2003 11:32:58 -0400
>> To: "Philip Atchley" <beaconeer at elite.net>, <Johnson at mailman.qth.net>
>> From: Roy Morgan <roy.morgan at nist.gov>
>> Subject: Re: [Johnson] Ranger keyer problem
>>
>> At 11:06 PM 10/22/03 +0000, you wrote:
>>
>>  
>>
>>> Incidentally, the two 1614 modulators test quite weak and with a 
>>> "life" test
>>> that drops.
>>>   
>>
>>
>> Phil,
>>
>> These 1614's are a problem.. they are expensive to buy if you don't 
>> have any (AES price is $30).  One possible substitute is the 
>> EL-34/6CA7 tube being currently manufactured at prices of about $12 
>> each.  The guitar guys and gals use lots of them.  There are two 
>> considerations:
>>
>> 1) Filament current. I just don't know if the EL-34 takes more 
>> filament current. It may.
>>
>> 2) Slightly different pinout.. the EL-34 *may* have a separate 
>> connection for the screen on pin 6 (I think it does).  You'd need to 
>> clear any connections on that pin being used as a tie point, and wire 
>> the pin to the right place (cathode, I assume).
>>
>> The current manufactured Tesla EL-34's are extremely rugged and I'd 
>> expect them to perform very well in the Ranger.  I do plan to look 
>> into this idea when I restore the Ranger I have here.  My Ranger has 
>> a kaput modulation transformer and burned tube sockets. It will get a 
>> replacement transformer I found, and ceramic sockets. This will let 
>> me make substitutions for the tubes as needed.
>>
>> I'd be glad to hear any ideas or more facts you may have on this.
>>
>> Roy
>>
>>
>> - Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
>> 7130 Panorama Drive, Derwood MD 20855
>> Home: 301-330-8828 Work: Voice: 301-975-3254,  Fax: 301-948-6213
>> roy.morgan at nist.gov --
>>
>