Cheap Accurate Sig Gen

[pwdrive]

http://www.s9plus.com/

(Multirock 2)

Lawrence

[Skywave]

Not a lot of £ for what it is and does, is it?
I can think of two useful applications for that, (in addition to the obvious ones and those listed) :

(a) as an enhanced calibrator for a short-wave radio;
(b) as a tunable local oscillator for a superhet radio.
Or . . . buy two: and do both!

Al.

[pwdrive]

Not a lot of £ for what it is and does, is it?
I can think of two useful applications for that, (in addition to the obvious ones and those listed) :

(a) as an enhanced calibrator for a short-wave radio;
(b) as a tunable local oscillator for a superhet radio.
Or . . . buy two: and do both!

Al.

I am tempted to have one of those, I always wanted to do a hybrid DCR with a DDS VFO, talking of which I built a DCR many many moons ago based on Spaargarens design but I can't for the life of me remember the coil details for the balanced mixer, so far as I can remember the coil I made was trifilar wound, primary was RF in, the two secondaries were connected as a center tapped winding which along with two diodes and a balancing pot formed the single balanced mixer, I remember that AM envelope detection could be virtually eliminated by balancing the mixer with the pot.
My design used valves and I think an EB91 or something similar was used for the balanced detector diodes
The link below is all I can find regarding Spaargarens design.
Can anyone remember this?

http://www.epanorama.net/sff/Radio/Commu...rt%201.pdf

Lawrence.

[AlanBeckett]

How accurate is it?
Presumably it depends on how good the onboard Crystal is. It's all very well dialling up 20MHz, but what actually comes out?

Alan

[pwdrive]

How accurate is it?
Presumably it depends on how good the onboard Crystal is. It's all very well dialling up 20MHz, but what actually comes out?

Alan

I would have thought 20 Mhz Alan, give or take a few cycles.
These ones seem to be popular:

http://www.pongrance.com/

Lawrence.

[AlanBeckett]

I fear young Lawrence that I remain cynical. It's all very well sticking some digits on an LCD, but that's no guarantee of accuracy.
I'd just like one of the Suppliers to quote a number, 1 Part on 10exp6 for example.

Alan

[Joe]

The fundamental problem is that it doesn't say "Advance" on it.

- Joe

[pwdrive]

The fundamental problem is that it doesn't say "Advance" on it.

- Joe

You can display "advance" in the alpha/num display if you wanted to.

Lawrence.

[pwdrive]

I fear young Lawrence that I remain cynical. It's all very well sticking some digits on an LCD, but that's no guarantee of accuracy.
I'd just like one of the Suppliers to quote a number, 1 Part on 10exp6 for example.

Alan

You can calibrate it to be as exact as as you want, this video might ramble on a bit for some but it shows how solid it is, note the frequency displayed on the SSB transmission, looks good to me, ditto for cw taking into account the the pitch frequency.
The receiver is a Ten Tec DCR receiver (I think) not a superhet

The DDS VFO would be excellent for determining the the Xtal frequency in a receiver Xtal filter without having to have safe crackers fingers thus would be a speedy aid to IF alignment in such receivers.

I'm convinced..

I want one.

Lawrence.

http://www.youtube.com/watch?v=0_0QtpHJwIY

[AlanBeckett]

.... note the frequency displayed on the SSB transmission ....

Arrrrrrrrr.
So it's got a lot of digits.
But how accurate is it?

Alan