[GreenKeys] Looking for VFO (1.5-2.0 Mc range) with FSK

Thu Oct 15 12:43:24 EDT 2009

Hi Roy and Russ -

Yep, the guy with 2 Northern Radio units would be me...  the "stock"
coverage of a Northern Radio type 105 model 4 FSK exciter is 2.5 to 6.7 mhz.
Factory change orders were issued to modify the units (if desired) to cover
1.75 to 4.5 mhz. The c.o. calls for replacement of some RF transformers AND
THE DIALS, so it's very easy to identify those units that have been
modified.

I don't remember off-hand, but I think both of mine have the lower frequency
coverage. The units are heavy, and consist of the keyer (35 lbs) and the
power supply (23 lbs). I have reconditioned and tested one set, but the
other, although complete, has not been powered up and I am holding it in
reserve for spare parts. I plan on using the 105 with my newly restored
BC-610 as soon as I run primary power to it. For frequency agility, I have
an operational Northern Radio type 115 Master VFO that matches the exciter.
My shack has Teletype 14/15/19/26/28 and Kleinschmidt machines that will
work through a switching matrix currently under construction. Hope to try
all of them on the air soon.

73's
john castorina WB6AZP (boatanchor at martasystems.com)
tty pictures at http://www.longandflatsociety.com

-----Original Message-----
From: greenkeys-bounces at mailman.qth.net
[mailto:greenkeys-bounces at mailman.qth.net]On Behalf Of wa3frp at aol.com
Sent: Thursday, October 15, 2009 12:52
To: k1lky at earthlink.net
Cc: greenkeys at mailman.qth.net
Subject: Re: [GreenKeys] Looking for VFO (1.5-2.0 Mc range) with FSK

Hi Roy!

Thanks for your email and for your thoughts.

The exciter in the Collins T-440/FRT-24 works as a frequency doubler on 80M
and 40M.  It further multiplies as the frequency increases.

The current VFO has a frequency range that starts at 2.0 and goes up to 4.5
Mc  That is fine for every ham band except 80M

If I can find a FSK Keyer that has an output at 1.75 Mc then I am fine.  80M
RTTY is generally between 3.7 and 3.6 with some countries like Japan
operating between 3.52 and 3.53 Mc

I suppose that I can modify and effectively eliminate the Collins doubler
circuit but that means I'll also affect 40M operation.

Thanks again,

Russ WA3FRP

-----Original Message-----
From: Roy Morgan <k1lky at earthlink.net>
To: wa3frp at aol.com
Cc: greenkeys at mailman.qth.net
Sent: Wed, Oct 14, 2009 11:36 pm
Subject: Re: [GreenKeys] Looking for VFO (1.5-2.0 Mc range) with FSK

On Oct 14, 2009, at 3:07 PM, wa3frp at aol.com wrote:

>
> Hi Guys,
>
> Turning to Greenkeys for ideas. My vintage (1959) TX is designed to >
operate 3 to 30 Mc but is mainly crystal operated. The current VFO > will
run the TX on 40M and up.
>
> But I would like to work some 80M RTTY this winter since the > sunspots
are still low.
...
> What I would like to find is a VFO with an output that covers 1.5 to > 2
Mc.

Russ,

If you can find a Northern Radio Company Type 105 F.S. Keyer, it would do
well for you. However, it's normal output is from 2 to 4 mc, and it
multiplies up to 32 mc, i am pretty sure. I seem to remember noticing that
they will tune from about 1.8 mc up. Just why you need 1.5 mc is not clear
to me.

To be frequency agile, then need an external oscillator, from 2 to 4 mc.
They have space for three crystals for fixed frequency operation.

In 2005, I emailed with fellow in CA who had two of the Type 105's (and
needed a manual). His email then was boatanchor at martasystems.com and he was
on this list. I have no idea if he'd let one of his go. But be advised these
things are HEAVY, and they need a separate power supply.

TMC also made an rf-output FSK keyer. They are harder to find, though.

Roy

Roy Morgan
k1lky at earthlink.net
529 Cobb St.
Groton NY, 13073
Home: 607-898-3607
Cell: 301-928-7794

=
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