[Boatanchors] Electronic T/R Switch

[rbethman]

Bob,

Envision a BC-610 or an RCA BTA-MX1 all packed in a cabinet with the 
same equivalent density!

You couldn't cool it enough to do ANY good at all!

The TR Switch has two tubes, both filaments constantly running, and it 
is trying to amplify the receive signal the whole time it is turned on, 
whether your receiver is turned on or not. 

The two page "manual" makes comment that the "hot to the touch" is 
normal. (LOL)

Bob - N0DGN

Bob Macklin wrote:
> I thought that might be the problem. I have seen many units over time that
> had the same problem.
>
> I remember some early solid state stuff that had heat problems because if
> inadequate ventilation. the designers thought that because there were no
> heaters no ventilation of fans were needed! LOL!
>
> Bob Macklin
> K5MYJ
> Kent (Seattle), Wa,
> "Real Radios Glow in the Dark"
>
> ----- Original Message ----- 
> From: "rbethman" <rbethman at comcast.net>
> To: <boatanchors at mailman.qth.net>
> Cc: "Bob Macklin" <macklinbob at msn.com>; <w8au at sssnet.com>
> Sent: Wednesday, November 05, 2008 11:49 AM
> Subject: Re: [Boatanchors] Electronic T/R Switch
>
>
>   
>> Bob,
>>
>> The heat is generated by the circuitry inside, not by the RF.  They get
>> just as hot simply sitting on with the coax attached.
>>
>> The cabinet is fairly tight around the components, with very little
>> holes that do not allow for much ventilation.
>>
>> A 12VDC muffin fan sitting on top, OR a 120VAC muffin with a dropping
>> resistor to reduce the speed will be immensely helpful.
>>
>> Bob - N0DGN
>>
>> Bob Macklin wrote:
>>     
>>> Where does the heat come from? I hopes it's not the Tx RF!
>>>
>>> Bob Macklin
>>> K5MYJ
>>> Kent (Seattle), Wa,
>>> "Real Radios Glow in the Dark"
>>>
>>>       
>> -- 
>> Bob - NØDGN
>>
>>
>>     
>
> _______________________________________________
>
>   

-- 
Bob - NØDGN

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