[R-390] HP 3589A and HP 140T

[Barry Williams]

Roy and Dave,

The 3589 was a typo and should have said 3580. I was thinking of the 
140A with 8555 and 5520 for frequency band analyzing, as like a 
panadapter. At one time, some of these units were somewhat cheap. It's 
been a couple of years since I was interested in this and I found the 
pics of these units yesterday on an old computer. The pic of the 3580 is 
from the *bay place where it was shown being used for that function. I'm 
not sure at this moment whether I would want to use either of these 
units with a R-390A or a HP 3586B....or with both.

I don't remember the comments that seller had regarding IF inputs, etc 
on the 3580A. I corresponded with him until the auction price went too 
high for me. I'll probably want to use one some of the time for MW/LF on 
the 3586A as that area is crowded.

Sorry to not have mentioned this earlier. BTW, how are you doing up 
there Roy?


Barry

>
> Barry,
>
> I've used the HP 8601A sweeper for aligning the Central Electronics 
> wideband transmitters (as helper to W0YVA, who has the sweeper and is 
> good at overhauling these things).  The 8601A covers from 100 kc up to 
> 110mc.  It's small, pretty easy to use compared to other larger HP 
> units, but fairly hard to find because it's so useful and easy to use.
>
> Of course a sweep generator plus a scope (and detector if needed) 
> comprise a rudimentary spectrum analyzer system without some of the 
> things a real spectrum analyzer does well.
>
> I have a fancier, bigger sweep generator, the HP-8690B, that normally 
> is found with microwave sweep heads plugged into it. Luckily, the hard 
> to find low frequency plug-in is the one I have.  This thing has a 
> slide rule readout the width of the unit, which is rack wide and 
> 10-1/2 inches tall.  It's moderately complicated to use and somewhat 
> confusing.  It's also a bear to fix if something is wrong with it.
>
> The HP 3300A is a function generator, but with the right plug-in it 
> will sweep 50/80 kc IF's just fine.  Actually, it goes from 0.01 Hz to 
> 100 kHz.  This is an older thing that may be available for not much 
> money. The needed sweep plug in is the 3305A.  If you find a frame 
> with a blank panel or another plug-in, it may be possible to get your 
> scope sweep output to sweep the thing in a remote control mode.  If 
> you can buy one at moderate price, don't pass it up. It will do all 
> you need to align IF strips under 100 kc.
>
> Roy

I know the 141T, not the 140T.  If the latter is not
a storage mainframe, it's much less desirable for spectrum
analyzer service than the 141T.  You wouldn't be able to
use the narrow resolution bandwidths, because they require
a slow sweep.

That's just the scope frame.  You
plug into it an 8552A or -B IF module
and an 8553L, -A, or -B RF module.  I'm familiar with
the 8553B and both 8552's.  The 8552B adds tighter
resolution bandwidths, better stability (required to
utilize said bandwidths), a "manual scan" mode, and
a 2dB log mode to supplement the standard 10dB log mode.

None of this is necessary for aligning our favorite radio,
but it's sure fun, and stuff of this vintage is not
expensive.  Beware that they're old enough to have
developed their own problems.  Unless you buy one
that's known-good (and maybe not even then!) don't
expect it to work without some sleuthing.

For measuring filter bandpass, you'll want a tracking
generator to go with the SA.  It'll be an 8443A or -B.
(Or an 8601A with Option <mumble> if the RF is an 8553L.)
In this case the -B is not an improvement; it's an -A
with the frequency counter section removed.  Early 8443A's
have nixie displays, which are cool in their own right.
Late ones have LED displays and interact more smoothly
with the SA, provided it's using an 8552B or a high-S/N 8552A.
The cable that interconnects these two is rare.  You can buy
a made-up one from glkinst.com for 100-some bucks or make your
own ugly but functional one for 1/4 to 1/2 that.  You will
probably have difficulty finding a parts guy who recognizes
the connectors.

HTH,