ANRITSU MG3641A signal generator

[alexo]

I'm looking for a spectrally clean signal generator with low phase noise. For a physics experiment. Anritsu pops up often on eBay. I wonder how good they are, if they are repairable ( parts ? ) and maybe some comments on possible alternatives.
I don't need more than 1Ghz but I would like to start low - around 200Khz or so.

[ratmandu]

I actually have one of these units on my bench right now, they work really well, and are pretty accurate (accurate enough for my work). If there are any tests you would like me to do, let me know. I have the MG3641A, with the DDS option, and a 200MHz agilent MSO-X 2014A scope.

[Johncanfield]

The HP-8640 has a reputation for a very clean output. They have a bunch of nylon gears that are known to break but there's a guy on eBay selling refurbished 8640s ( I bought one from him.)

[metrol12]

Alexo,

Low Phase noise performance is subjective.  If you could provide what typical phase noise characteristics your experiment would need in noise performance at various frequencies you will be testing.   That way we can comment on various generator available.

[alexo]

The HP-8640 has a reputation for a very clean output. They have a bunch of nylon gears that are known to break but there's a guy on eBay selling refurbished 8640s ( I bought one from him.)

That one was on my list but they're OLD. And I'm real bad at RF - little chance I'll be able to fix it. I could make the gears though, pretty easily. And there is something else - it starts pretty high at around 450Khz. It's not that I need lower but I'd like to have there just in case...

[alexo]

Alexo,

Low Phase noise performance is subjective.  If you could provide what typical phase noise characteristics your experiment would need in noise performance at various frequencies you will be testing.   That way we can comment on various generator available.

Good point. I'd like to be SURE of 140dBc/Hz at 500Mhz. And I mean dead sure.

[alexo]

I actually have one of these units on my bench right now, they work really well, and are pretty accurate (accurate enough for my work). If there are any tests you would like me to do, let me know. I have the MG3641A, with the DDS option, and a 200MHz agilent MSO-X 2014A scope.

Unfortunately  I think I'll have to stay away from those ones. The Anritsu MG3633 looked like the winning horse but if it breaks, I'm stuck with a 30Kg brick. I found that the only one I can hope to have fixed would be a Rhode & Schwartz SMB/V . Bad news as they cost money.

I LOVE the look of the 3641 but my budget won't cover half of one anyway.

[B1nary]

The HP-8640 has a reputation for a very clean output. They have a bunch of nylon gears that are known to break but there's a guy on eBay selling refurbished 8640s ( I bought one from him.)

That one was on my list but they're OLD. And I'm real bad at RF - little chance I'll be able to fix it. I could make the gears though, pretty easily. And there is something else - it starts pretty high at around 450Khz. It's not that I need lower but I'd like to have there just in case...

I've been looking for a generator to do an alignment on my Revox B261FM Tuner so can you say who the guy is? There's a few on there and most look in bad shape. What I'd really like is something a whole lot newer than the 8640 or the Sencore SG165. If anyone had suggestions .....