[R-390] Sweep generator wanted.

[mikea]

On Sun, Jan 27, 2008 at 01:53:25PM +1100, Pete Williams wrote:
> 
> G'day USA.... wanted is  a HP 8601A sweep generator.... got  some Racal
> needing a check over  for one thing .
> Yep, been to the  bay but never found the water cool enough.! Any lying
> around superflous to requirements ?
> Tks 
> Pete
> jupete at bigpond.net.au

I've got a dodge for you, if you've got an HP 8640B or other generator
that does DC-input FM and you have or can build a linear ramp
generator:

run the output of the ramp generator, DC-coupled, into the FM-mod-in 
jack of the 8640B, set the unmodulated freq for the low end of the
sweep range (for a +-going ramp starting at 0V), and then set the 
modulation gain pot on the 8640B so that the high end of the sweep is
to or past the range you need swept. I also use the ramp as x-axis 
drive on my scope, so that I see the output from the DUT as a true
response curve. It works a treat, 

My 8640B goes down to about 450 KHz, which is good for most IFs, and 
up to about 1.2 GHz, which is a bit better than the 110 MHz of the 
8601A. 

Ramp generator schematics are available on the web, though I use my 
sweep generator's ramp output -- which is fudging, I admit, but it 
still works. 

Just in case you can get an 8640B and not an 8601A. 

-- 
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin