To: softrock40@yahoogroups.com
From: "kb9yig"
Subject: [softrock40] SoftRock v6.0 - 80m / 40m operation

Several have been concerned about the SoftRock v6.0 idea of selecting
between two harmonically related bands such as 80m and 40m by only
changing the clock divide ratio. The divide ratio would be divide by
four for 40m and divide by eight for 80m. The BPF would be made board
enough to span the two bands. The concern was that strong 40m signals
would be in the 80m spectrum when 80m operation was selected.

I have been observing the 40m and 80m operation this evening with the
first of the v6.0 SoftRock receiver examples. I find that even 20
over S9 signals on 40m do not appear in the spectrum when 80m
operation is selected. I believe this suggests good balance in the
v6.0 QSD circuit.

I am happy to report that it looks like two band operation, at least
for 80m and 40m, results in good receiver operation. Bill, KD5TFD,
will be evaluating the performance of the first prototype next week
and will post measurement numbers on MDS, dynamic range and
40m "leakage" to 80m at large signal levels.

The eight first responders to the v6.0 prototype kit announcement have
been sent e-mail offers to receive a prototype kit. That will be all
the prototype kits I will have to send out.

Good chance that I will be in a position to start shipping production
kits by the end of March if the prototype evaluation goes well.

Thanks and 73,
Tony KB9YIG

To:
From: "Tony Parks"
Subject: Re: [softrock40] softrock V6 on 20M

Hi Ray,

The problem with the v6.0 SoftRock getting to 20m is the need for a
fundamental crystal 4x times the center frequency you want on 20m. Another
way to get to 20m is with 3rd sub-harmonic sampling. The crystal frequency
then needs to be (14.24/3)*4 = 18.987 MHz . The BPF needs to be for 20m and
probably with a more narrow response than the BPF in the v5.0. The
sensitivity of the v6.0 used this way will be down 6 dB but I think it
should still be as sensitive as the v5.0 on 20m. Worth a try anyway, I
think.

73,
Tony KB9YIG




To:
From: "Tony Parks"
Subject: [softrock40] 17m SoftRock Lite info

Hi Loren,

I tried sending the message below this morning only to have is bounce back, thus the posting
to the Yahoo group.

I looked at the 17m SoftRock Lite filter this morning and reasonable
component changes would be to leave L1 and T1 winding turns the same as the
20m SoftRock Lite (T25-6 cores, yellow) and change the BPF capacitors to be
C21=33pF, C22=470pF. The capacitors in the oscillator circuit, C3 and C4,
can stay the same as the 20m SoftRock Lite. R6 might be needed depending on
the crystal activity.

Hope this helps.

73,
Tony KB9YIG

To:
From: "Tony Parks"
Subject: Re: [softrock40] Softrock on 5MHz

Hi Roger,

Here are a set of component values that should be ok for the SoftRock Lite on 5 MHz.

L1 43T of #30 on a T25-2core (6.3 uH)
T1 10T of #30 on primary and 5T of #30 in each of the two secondary
windings "bifilar" over the top of the primary on a T25-2 core (0.35 uH on primary)
C21 150 pF
C22 2200 pF

73,

Tony KB9YIG