[time-nuts] General questions on 8510C network analyzers

[Javier Herrero]

Hi, Tom,

Thanks for your comments. Generally speaking, my VNA needs are quite 
ocassional, so even a new ENA would be difficult to amortize :) although 
I see it is a nice machine - but surely in the price range of a good car 
(I've a price reference of around 28000 EUR for the 1.5 or 3GHz E5061B, 
not sure which). I see that they also cover quite low frequencies, that 
the 8510C does not, but for that purposes I already own a venerable 
3577A - with a minimum frequency of 5Hz, and 300kHz with the 35677A 
S-Parameter unit :)

Other reasons why I'm in preference of an8510C instead of A and B is 
that it seems to use a not so rare CRT (a colour one, so I suppose that 
it has not the issues commonly related with the 8566 spec. an.), but 
perhaps I'm not right. I've not seen about an LCD replacement as for the 
8566, but being a raster display instead of a vector one, probably would 
not be hard to extract the video signals and drive an external monitor 
in an emergency.

I see that for the sweeper it is desirable a synthesized one, and 
although my current need is not very demanding on frequency accuraccy, 
it will be a probably best investment for the future.

As for Opt 10 - time domain, I remember to have read long ago that it is 
a purely software option, enabled through a PLD (but this is something 
heard or read long ago when I was not so interested on 8510s so I could 
be very wrong). For now, I would not need it - but as usual, a nice 
thing to have.

Best regards,

Javier, EA1CRB

El 05/07/2011 20:50, Tom Holmes escribió:
> Javier...
>
> The 8510 IS a great box, but I would be concerned about the combination of
> advancing age and availability of parts, especially CRT's and
> attenuators...actually, anything mechanical. You could buy spares at
> auction, but those would likely have the same problems. Manuals are fairly
> easy to find.
>
> As for the sweeper issue, it may not have been in the earliest models, but
> the later ones have a stepped sweep mode that actually does issue specific
> frequency commands to the LO for each measurement point. Slows things down a
> bit but very accurate and repeatable in frequency. That being said, the old
> 'lock and roll' scheme was not all that bad for frequency accuracy, unless
> you are a time nut ;-).
>
> And if it has the time-domain option, rejoice!
>
> Agilent also has an ENA line which is less expensive than the PNA line, and
> it offers a 20 GHz model which is as capable as the 8510, actually more so
> in many ways. The savings in maintenance headaches might be worth the extra
> up-front cost. Things like speed, dynamic range, number of points available,
> and noise floor are all much improved over the 8510.
>
> I have seen where there is an LCD replacement display for the 8566 series
> spec an which might also work in the 8510 if the CRT goes out.
>
> Tom Holmes, N8ZM
> Tipp City, OH
> EM79