Gigatronics GT9000 20Ghz Microwave Synth Manuals/Service Information

[NyquistNoise]

Hi All,

I've currently got a Gigatronics GT 9000 Microwave Generator on the bench for repair and am struggling to find a complete service manual. There seem to be lots of digital copies of the operation/service manual around on the web, however none of them seem to have Chapter 7, the chapter with all the schematics!
It appears that the paper copy of this manual has chapter 7 in nice pull out A3 pages, so I assume that's why they skipped putting this in the digital version.
I'm mostly after the downconverter/A16 schematic, as I'm having PLL lock issues below 500MHz at it appears at these frequencies this board handles the LO

If any kind hearted people out there happen to have the paper version of this manual/Gigatronics gurus who know this kind of fault have any information I'd be eternally grateful - starting to go mad stabbing in the dark at this fault!

TIA! 

[NyquistNoise]

So it seems I've mostly solved this one myself  the Gigatronics 7200 is a very similar instrument, and shares a lot of the same PCBs, and this service manual is available on K04BB - So if anyone else is trying to repair a GT 9000 and wants schematics try here!

[NyquistNoise]

Continuing my little thread here - for those that are interested, I had an LO unlock issue below 500MHz, which is downconverted.
Following what I found in the schematics, I actually found out one of the SMC connectors on the downconverter board is supposed to carry a 1.666MHz or 5Mhz IF signal - but was totally missing! This explained the unlock issue.
This lead me to the A201 board, which generated the 1.6 and 5 MHz IF using two identical circuits which fed different parts of the synthesiser. One of which was working, and the other (the one used by the downconverter PCB) was not.
Following the signal (or lack thereof!) Ended up leading me to the "sampling mixer" RF block, which on very close inspection, revealed that some wire bonding which is normally attached to the step recovery diode, was no longer attached!
As I have no ability to do any wire bonding, this is the end of the line for the <500MHz range!

If anyone is scrapping/selling for parts and Gigatronics gear, you may have an interested buyer here

[DaJMasta]

You do see these older gigatronics generators on ebay sometimes, and I've seen sellers trying to pass off smashed up units as "for parts" - maybe in your case that could actually be useful and if the face is smashed in they'll probably cut you  a decent deal 


They seem to be much more common than more recent gigatronics generators, for which I haven't seen any service information nor software.