Yes, we could swing the grids of those tubes quite a ways before
encountering enough non-linearity to produce a significant amount of
intermod, Andy! The old original AMECO tunable vacuum -tube preamp, that I
borrowed from Bill, K4CIA, worked really well with my KAZ terminated RX loop
for the low bands. It was connected to the receive antenna port on my
FT-1000MP, so I wasn't blowing FETs!
My electronic design career began before the end of the vacuum-tube era, and
I used the 6DJ8 commercially in some VHF monitor receivers, as a cascode RF
stage in the front-end.
73,
Charlie, K4OTV
-----Original Message-----
From: Andy Ikin [mailto:andrew.ikin@btopenworld.com]
Sent: Sunday, August 25, 2013 5:16 PM
To: Charlie Cunningham
Cc: Topband Reflector
Subject: Re: Topband: Anyone have a boat load of J-310s?
Thirty years ago I used 6DJ8 (E88CC) to solve a third order IMD problem with
tuned loop that was using J310s.
The IMD was caused by Radio Free Europe on 13m.
73
Andrew
----- Original Message -----
From: "Charlie Cunningham" <charlie-cunningham@nc.rr.com>
To: "'Andy Ikin'" <andrew.ikin@btopenworld.com>; "'Topband Reflector'"
<topband@contesting.com>
Sent: Sunday, August 25, 2013 9:14 PM
Subject: Re: Topband: Anyone have a boat load of J-310s?
> Of course, a 12AT7, or better, a 6DJ8, would be excellent preamps as
> well,
> and aren't so sensitive to transients etc. :-) (Showing my age, I
> guess!)
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Andy
> Ikin
> Sent: Sunday, August 25, 2013 3:58 PM
> To: Topband Reflector
> Subject: Re: Topband: Anyone have a boat load of J-310s?
>
> As far as am aware On-Semi still make the TO-92 J310. Fairchild ceased
> production about 2 years back. I did a last time buy from Mouser for
> several
>
> thousand J310 and the much more linear J309.
>
> 73
>
> Andrew Ikin G8LUG
>
>
> _________________
> Topband Reflector
>
> _________________
> Topband Reflector
>
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Topband Reflector
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