I have a Motorola manual, from the 70's, what is an 8877, 2 to 18 mhz HF amp,
using relays for the Pi switching. Part list says "special modified relay". The
fuzzy photo looks like just 10 amp contact, open frame P&Bs. Think the mod is
just a strap across the DPDT wiper. Getting ready to think about planning to
try it with a pair of 813's or 572's.
Someone with a bigger brain do the volts and amps math.
Bob, K2RK
Sent from my iPad
On Aug 7, 2010, at 7:35, Lee Buller <k0wa@swbell.net> wrote:
>
> Jim, thanks for your excellent work and commentary.
>
> Now, the question I have....
>
> Do you think these relays could be used in switching a PI-Net circuit in an
> amplifier instead of the standard rotary switch?
>
> Finding a suitable band switch for a legal limit amp is rather daunting and
> expensive. RF current in the PI_Net could be extremely high if I remember
> correctly...on the order of 25 amps or so...but I could be wrong. The relays
> could be used to switch coil segments in or out and adding capacitance to the
> tune and load controls. What strikes me as interesting is that you could set
> up
> a BCD diode matrix to control band switching with relays. That could be
> coupled
> to a transceiver for automatic band changing.
>
> Comments?
>
> Lee Buller - K0WA
> "A liberal arts major and a wannabe engineer"
> --------------------------------------------------
>
>
>
--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|