[time-nuts] HP5370 power supply measurements
bruce.griffiths at xtra.co.nz
Wed Jul 13 05:04:57 EDT 2016
The most effective approach would be to design a replacement with lower jitter (< 5ps ) and lower power consumption (< 10W??).The hard/interesting part is the higher resolution lower jitter interpolator.Preliminary testing suggests this part isnt as difficult as first thought.
As soon (within a month or so??) as I finish repairing a 24" Cassegrain secondary mirror mount, I'll get back to this.
From: Charles Steinmetz <csteinmetz at yandex.com>
To: time-nuts at febo.com
Sent: Wednesday, 13 July 2016 7:11 PM
Subject: Re: [time-nuts] HP5370 power supply measurements
> So I've been playing around with KICAD and come up with a design
> with three Traco TEN40WIR DC/DC converters (2x2411 + 2423) running
> off the +/- 10V rails, and I'm seriously tempted to try order a
> PCB just to try it out...
Are the Traco converter modules cheaper where you are than here in the
US? It looks like the three converters would cost more than $360 here
-- almost double what I paid for my most expensive 5370B. I recognize
that you get a fair amount in the package, but the regulation and noise
specs -- while OK -- are certainly not stellar.
An external fan blowing on the heatsink keeps my 5370s nice and cool,
for about $10 each. The ones I use are 120v, clamp-on types sold for
making a breeze at a workstation, and are extremely quiet. The
heatsinks run barely warm to the touch.
Reducing line consumption by 50w would save about $3 per counter per
month here, assuming 24/7 usage. Break-even on the cost of the
converters would therefore be ten years, *if the counters were operated
24/7/365*. I sometimes take data for a few months straight, but very,
very far from 24/7/365 on average. So for me, break-even would be more
like 50 years. Even if you pay a lot more for electricity than we do
here, it's still a very long time before you break even.
Speaking of fan noise -- you can't really get away with replacing the
internal fan with one that moves less air, so it is hard to find a
replacement that generates significantly less noise. If you find one,
please share the make and model -- all 5370 owners would love to know.
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
More information about the time-nuts