[time-nuts] HP 5245L counter circa 1967 humor

paul swed paulswedb at gmail.com
Sat Jan 9 21:10:01 UTC 2010


Thanks they do indeed pull out. I was hard pressed to believe that HP
wouldn't design it that way.
The one was very tight that I was trying. Swapped with another and indeed
that nixie is bad.
May try lowering the 47K from the 170V a drop on that tube to see if I can
revive it.

On Sat, Jan 9, 2010 at 1:04 PM, jmfranke <jmfranke at cox.net> wrote:

> For the 5245L, the Nixies pull straight out of their sockets.  They pull
> out perpendicular to the faceplate.
>
> John  WA4WDL
>
> --------------------------------------------------
> From: "paul swed" <paulswedb at gmail.com>
> Sent: Saturday, January 09, 2010 12:29 PM
> To: "Discussion of precise time and frequency measurement" <
> time-nuts at febo.com>
>
> Subject: Re: [time-nuts] HP 5245L counter circa 1967 humor
>
>  Very very interesting read on hollow leads. Like you I also had spares in
>> the conductive foam and learned the same thing. Very bad indeed.
>>
>> I do need to look at several of the decoders to nixies they are acting
>> strange and would easily guess that the neon bulb logic has some flaky
>> bulbs. I started opening that section up and stopped. Its going to be a
>> fair
>> job. It will be really curious how did they get all those little photo
>> resistors around the neon bulbs? Though with humor a 74ls90 cntr 7475
>> latch
>> and 74141decoder would eliminate all of that, but thats not how the unit
>> works. hate to hack it that way.
>> Anyone know if the burroughs nixies just pull out of the socket? At least
>> I
>> think its a socket.
>> I tried and they did not let go. I want to separately test the nixie I
>> think
>> its actually OK.
>> Thanks
>> PS I don't see carcasses anymore at flea markets. More importantly no test
>> equipment anymore. The ebay effect.
>>
>> On Sat, Jan 9, 2010 at 10:46 AM, David Forbes <dforbes at dakotacom.net>
>> wrote:
>>
>>  At 9:59 AM -0500 1/9/10, Gary Chatters wrote:
>>>
>>>
>>>> The 5261A Video Amplifier plug in will get the sensitivity down to 1 mv.
>>>>
>>>> The 5258A Sensitive Prescaler will also get the sensitivity down to the
>>>> 1
>>>> mv range as well as extend the upper frequency range to 200MHz.
>>>>
>>>>
>>>>
>>>> Gary
>>>>
>>>>
>>> Gary,
>>>
>>> Thanks for the idea. I'll look for those plugins. I actually remember
>>> thinking about getting the video amplifier many years ago, but that was
>>> in
>>> the year 6 BE (before ebay).
>>>
>>>
>>> --
>>>
>>> --David Forbes, Tucson, AZ
>>> http://www.cathodecorner.com/
>>>
>>>
>>> _______________________________________________
>>> 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.
>>>
>>>  _______________________________________________
>> 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.
>>
>>
> _______________________________________________
> 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 mailing list