I have not looked at the CSR 5 handbook but suspect you have the order of the RF reversed.?

The other tubes , like the 1853, are really not like the 6SG7.? They were designed for wide band television IF use.? As RF tubes they have rather low impedance making it difficult to get good selectivity .??

I have lost a word,? means non-beluever,? but I think the well loved SX 28? has some serious design flaws.? Hallicrafters liked to use hot tubes but they were not always used well.?

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-------- Original message --------

From: Jacques_VE2JFE <jacques.f@...>

Date: 10/28/22 11:11 AM (GMT-08:00)

To: [email protected]

Cc: 'Richard Knoppow' <1oldlens1@...>

Subject: Re: [HallicraftersRadios] SX-110 2nd IF Circuit Design

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About the 6SG7…

Another receiver from the same Era than the RCA AR 88 is the Canadian Marconi Co. CSR-5A.

1^st RF: 6SK7, 2^nd RF: 6SG7, 1^st IF: 6SG7, 2^nd IF: 6SK7.

The CSR-5A is also the first receiver (to my knowledge) using a miniature tube in the local oscillator: a 9002.

From 1943, the RCA AR-88LF became the Canadian Army “standard receiver” but the CSR-5A became the Royal Canadian Navy counterpart.

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There is also more tubes that are close to the 6SG7 characteristics, including the 6AB7 (1853) used in the SX-28/28A.

See:

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Richard Knoppow wrote?:

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