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I'm keeping watch for an HP-8662A or HP-3335A as an all-around frequency
source for my bench.

Most of what I do ranges from DC to 148 MHz, and about the most complex task
I think I'd do is sweep an IF filter or align a rig. I'd like to use it as
an outboard tracking generator for my HP-8591E also.

I like being able to spin a knob and change frequency ... to rock back and
forth to find an IF center frequency, for example.

Give the application, am I better off with one of the above units vs. the
other? Something else? Price IS a considertion.

Thanks, and forgive me if this has been "asked and answered".

Jeff
W8KZW

HP 8165a. Not sure it'd work with the SA, though. I drive mine with GPIB.
Usually can be had cheaply.
Norm

On Sun, Jan 6, 2013 at 12:36 PM, W8KZW <w8kzw@...> wrote:

**



I'm keeping watch for an HP-8662A or HP-3335A as an all-around frequency
source for my bench.

Most of what I do ranges from DC to 148 MHz, and about the most complex
task
I think I'd do is sweep an IF filter or align a rig. I'd like to use it as
an outboard tracking generator for my HP-8591E also.

I like being able to spin a knob and change frequency ... to rock back and
forth to find an IF center frequency, for example.

Give the application, am I better off with one of the above units vs. the
other? Something else? Price IS a considertion.

Thanks, and forgive me if this has been "asked and answered".

Jeff
W8KZW

[Non-text portions of this message have been removed]

Hi Jeff,

I can strongly recommend the 8642B although its frequency range substantially exceeds the 2 meter band. That unit is my favorite for receiver work and it will meet all the criteria you mentioned in your post. Of course, used as an external tracking generator, it will operate at a sweep speed which is not synchronized with your SA, but depending upon your desired frequency span it could do an excellent job with the 8591E (which I also own.) The top end of the 8642B is 2.1 GHz which exceeds the 1.9 GHz top end of the 8591E.

I would not recommend the 3335A on the basis that the top frequency is 80 MHz and the minimum RF output is -87 dBm so you will need to use an external attenuator for front-end work. Its strong point is that its calibrated RF output is supposed to be extremely precise, within 0.09 dB. I use that to confirm dBm calibration of my SA at lower frequencies.

I would not recommend the 8165A on the basis that the top frequency is 50 MHz, its frequency stability is relatively poor, and minimum RF output is 10 mV p-p. If you listen to the signal on a SSB or CW receiver, or connect to your SA, set to a narrow bandwidth, you will hear/see the carrier frequency moving around. To further demonstrate how unsuitable it is, the spec sheet actually has a "jitter" spec of 0.1% at frequencies above 1 kHz. I had never before seen a jitter spec on a function generator or RF signal generator. Had I known about that in advance, I would not have bought this unit.

The 8165A is basically a function generator that has a couple of interesting twists: you can have it produce a specific number of pulses, and you can set the duty cycle to 20%, 50%, or 80%. It has no provision to connect an external 10 MHz frequency reference, although that would be useless since the jitter is so pronounced. I own a unit with the option that allows AM and FM modulation.

Good luck with your choice.
73,

Patrick Wong AK6C

Hi Jeff,

I doubt you want an 8662A for general purpose applications. I own two, plus two "donor units". They are great when you really need low phase noise, but have downsides.
1) They are huge and heavy.
2) They are very complicated. Lots of little boards living in cavities in an aluminum casting. Difficult to troubleshoot without extender cards.
3) They are not really reliable. A later model might be better, but the old ones were not (say 1985). I don't think it was design so much as complexity and time.

I also own 3 Fluke 6070 and 6071 synthesizers. The 6070 is 512MHz and the 6071 is 1024MHz. These are also big, but have been more reliable and have a better user interface (my opinion). I also think they are simpler and easier to work on. Phase noise above 10KHz is better than the 8662 - below it is quite a bit worse. Downsides are that they are orphans - but Agilent doesn't provide any support for the 8662 either.

I am not sure what you expect from the source. Remember that these things are programmed by microprocessors and you will see glitches as the loops are retuned. You may see clean sweeps on small steps away from areas where a bunch of things get reprogrammed.

Fluke produced a number of other synthesizers, but they were designed for a lower price point. They may be more than adequate for your application. Maybe someone else can comment.

Lew

Hi Jeff,

Look for a working 8648A. I like the clean, simple operational front panel control of these units. Has all the features needed for HF, VHF and UHF work to 1GHz.

Regards

Gerald
VK3GJM

Jeff,

The 8662A is a very nice low phase noise box with sweep up to 1280MHz but is very heavy (hard to ship) and not so reliable or easy to fix. I have 2 working units plus a parts carcass. I have no personal experience with the 3335A. Good luck with what ever you purchase.

Regards,
Eric