It seems like it would be very tight in a single plug-in, if it even fits. A
dual PI would certainly work though.
Also, as someone pointed out, the TM-500 series may not have the power and
cooling available. I have. TM-5006 chassis that would certainly do the job in
both regards, but that's the last thing I would want running 24/7 in my shop...
My LPRO found a spot in an old HP bench voltmeter chassis, and runs from a
recycled laptop power supply (that way, the heat from the supply is not
dissipated in the box). The installation is not complete, but I intend to
install a small computer fan to keep the air moving through holes in the
chassis.
I will then use a modified T-Bolt Monitor to monitor the parameters from the
LPRO, and the temperature via a front panel display.
Didier KO4BB
Sent from my Verizon Wireless BlackBerry
-----Original Message-----
From: d.sei...@comcast.net
Sender: time-nuts-boun...@febo.com
Date: Thu, 16 Sep 2010 19:57:09
To: Discussion of precise time and frequency measurement<time-nuts@febo.com>
Reply-To: Discussion of precise time and frequency measurement
<time-nuts@febo.com>
Subject: Re: [time-nuts] LPRO101 orientation vs lock
Hi Bob-
I don't have the LPRO in a plugin, but I had considered it, and was wondering
if any of those that had built one had thermal and/or lock issues.
Re the sun in our valley... not this year! My tomatoes just started really
producing and my squash and zucchini still haven't even flowered. That has
NEVER happened to me before. A very odd year weather-wise!
Dave
----- Original Message -----
From: k6...@comcast.net
To: time-nuts@febo.com
Sent: Thursday, September 16, 2010 8:07:19 AM
Subject: Re: [time-nuts] LPRO101 orientation vs lock
I assume you mean Tektronix TM5xx or 5xxx modules.
I haven't seen an LPRO plugin, but considered doing one for my TM506 rack. My
conclusion was that I couldn't get rid of enough heat without cutting custom
fins for the LPRO.
Recall that the physics package in the LPRO is the biggest source of heat, and
looking at the unit with the connector facing you and on the left, the physics
package is along the right side toward the rear of the unit. I decided the way
to mount the LPRO if I had to go vertical was with the physics package closest
to the top, to minimize the components that got baked. (I welcome recalibration
of this opinion from more knowledgeable sources!)
If I could cut fins for the new "top" edge, as well as a good plate for the
bottom, and some fans, i might be able to get rid of enough heat to make it
work. I considered mounting the LPRO to the rear of the module connectors, in
the area containing the linear power supply components.
I reconsidered on recalling admonishments in the LPRO docs and on this list
that cesiums do not like magnetic fields! Mounting the unit next to large power
transformers wouldn't seem to be suck a good idea...
You might have better luck running it in a TM5006 rack, as they have much
better cooling and airflow (a reason to get rid of that 506 and pick up a
5006!).
I've had good results with my LPRO mounted on a half inch plate of T6061
aluminum and an old AMD heatsink+fan mounted above the physics package, held in
place with arctic silver heat transfer compound and spring-loaded wire clips
going to the plate. I've been meaning to run noise studies to see if the fan
causes any problems (vis a vis mag fields).
Since I expect to be using the LPRO only occasionally, I've been trying to talk
my son into making me a steampunk-themed case, something like rosewood with
brass corners and detailing...
Cheers and 73 -- Bob K6RTM in sunny silicon valley
On Sep 16, 2010, at 2:51 AM, d.sei...@comcast.net wrote:
> I got one of the ebay LPRO-101s about 6 months ago and played with it for a
> while, but had problems maintaining a lock. First of all, it has a heat sink
> bolted to the bottom that is just a little larger than the LPRO itself,
> including being about 1.25" thick( 1" fins). Typical frequency when locked is
> 10,000,000.007 on a 5360A clocked by a Z3801A.
>
>
> Both then and now, it takes about 45 seconds to lock from cold, and will stay
> locked for about 45 minutes. I found that in the position with the heat sink
> on the bottom will stay locked the longest (up to a few days), but then it
> becomes intermittent. Other positions will lock for a while, but bottom down
> always works the longest.
>
>
> For those of you who employed these in TM5xx or similar plugins, did you have
> lock issues? Is my unit just old?
>
>
> Dave
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
------------------------------
_______________________________________________
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
End of time-nuts Digest, Vol 74, Issue 77
*****************************************
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
