Signal Generator Boards:

[Electrical Rod]

These boards and the others I pulled came out of what I considered to be a type of high end signal generator for the time.

I can't remember the name or the model number either. Found the dead generator at a flea market for cheap 15 or 20 years ago. I took a short look at it and found voltage regulator, power supply issues.

The best I can remember this unit went way up into VHF range and down to less than 100 khz.

I pulled all the boards and some other parts, etc. From the photo I only show three, so just wondering how to wire one up for the lower frequency range boards, when I can determine what is what, and possibly make some sort of frequency standard, if possible.

Rodney

[CambridgeWorks]

No idea as to maker or circuits. All I can say is it does not look like high end to me.
Rob

[Herald1360]

Hermetic looking feedthroughs and SMA type connectors looks high end to me. Scruffy condition but expensive looking construction at any rate.

[CambridgeWorks]

My comment was mostly about the state it is in now, looking rather rough. Don't look like sma, can't think what they are called. I have a few odds and ends....somewhere. The module on right looks unmolested. The top one looks totally rebuilt with newer components throughout, probably been experimented with? Bottom looks like tinplate has been mauled quite a bit, but otherwise look like original components. Wonder if it has "Whiskers" growing within. Be interesting to see the rest of the modules. Some of the original components (trimmers and the resistors) look European origin maybe?
I think even with the original manual there is quite a challenge to make a frequency standard. If the original reference oscillator is still there, it would be a good start. Probably as the basis of a new design entirely.
Rob

[CambridgeWorks]

Just a thought, not from a Schomandl frequency standard, type FD100?

https://www.google.co.uk/search?q=sc...v_rxWIAqxYNLM:

I used to have one, a grey box, about 18" wide, 7" high and 10" deep. A row of about seven decade switches. Used for generating dial up frequencies in mobile radio workshops. As well as generating a carrier, you could also input a signal and hear the audio beat note. I wonder if the OP recognises the picture link? Nearly all other google pictures are the very early one, which is an upright model.
Rob

[Electrical Rod]

Included is a photo of what i call the mother board, may be called something else, I just used mother board for photo identification only.
The other 6-8 boards are similar to the first three but different, all of them slide into a metal can and screwed in from the back, the best I can remember the cables, wires and connectors were screwed in with these mico-fittings.
None of those were easy to take apart, no doubt they were sealed good. I have used several good transistors and other parts from some of these boards.
Rodney

[Diabolical Artificer]

Not off a Wavetek by any chance? The boards haven't aged well and it's going to be interesting getting them working without a schematic/block diagram.

Are there any "special" IC's in it like ASIC's that might have the makers part ID on. HP and Tek rolled their own chips, might give a clue.

From the chips ont mother board it was made circa 81.

Andy.

[Radio Wrangler]

50 ohm SMC connectors? (there is also a 75 ohm SMC which is much larger in diameter)

The 'mother board' looks like just the frequency control registers. Looking at the chip types might find some BCD up/down counters at a guess.

If it's got a lot of similar modules, it may be an iterative synthesiser, the so called 'Direct synthesiser' not to be confused with the direct digital synthesiser (DDS). There's a description in the synth chapter of the ARRL handbook, any year 1995 onwards.

David

[CambridgeWorks]

Just seen gave the wrong link. Should have been
https://www.google.co.uk/search?q=sc...08.cIMaP4bZT18
The FD100, if the picture jogs your memory at all.
Yes, David, SMC is what I first thought. But not being certain used google images which showed mostly SMA, so I wasn't sure.
We used a lot of SMA and SMB where I worked, all gold plated. They chuked loads of pre-assembled new leads out, I still have a few. Even if only for 450Khz!
Those SMC in the first picture are not gold plated, so maybe a more "domestic" piece of kit?
Rob

[Stockden]

Originally Posted by Diabolical Artificer

Not off a Wavetek by any chance?

I think you're right Andy, these looks to me like the modules from a Wavetek 3000 series generator. .

I had one of these and it drove me mad trying to track down faults. Like much equipment of that period it suffered from shorted tantalum capacitors and the complexity of control loops within control loops made fault identification harder. Oh and having the modules inside cans that were soldered shut added to the fun.

On the other hand it was great when it worked and, as I recall, most of the components were standard types (a lot of 8 pin op amps for instance).

Hugh

[CambridgeWorks]

I only ever had 1 Wavetek and it was a sweep generator. Upto 2.5Ghz maybe?
Yes, though quite old and with filmstrip scale, it had some plug in modules. ISTR for the different marker options.
Rob

[Diabolical Artificer]

That's the one Hugh internal pic here - http://ebay.davidnavone.com/ebay9e/Wave2.jpg

A.

[Electrical Rod]

I remember now, thats it, WaveTek., 1980`s,, someone else said they could be a big problem to work on as I recall.
I will just keep some of the parts around and go with several other options. That one is beyond my ability anyway.
Thanks for the ID
Rodney

[Radio Wrangler]

That general era for this sort of thing was fraught with unreliability. You may be better off starting again from scratch.

David

[Nymrod121]

I used to have one, a grey box, about 18" wide, 7" high and 10" deep. A row of about seven decade switches. Used for generating dial up frequencies in mobile radio workshops (snipped)
Rob

Yep, still got it Rob - plus all the circuit info you kindly provided when we met up at Princethorpe a couple of years back
Guy