Re: 141T reference replacement..a cure??
That link ain't gonna work, its to a file local on your computer!
FWIW, there is no metal film resistors in the 141T, but there is a lot of carbon film resistors! Those should not be mixed up, as their preformance is quite different.
BR. Thomas.
?
These tubes were designated as Z82R7. Spec sheet is at folowing link.
>>> file:///C:/Documents%20and%20Settings/Administrator/My%20Documents/Downloads/Signalite-Hivac%20neon%20regulators-LM317.pdf <<<
Who would think replacing this obsolete tube would cause such an upstir!
Dennis
--------------------------------------------
On Sat, 7/15/17, Jeremy Nichols jn6wfo@... [hp_agilent_equipment] <hp_agilent_equipment@yahoogroups.com> wrote:
Subject: Re: [hp_agilent_equipment] Re: 141T reference replacement..a cure??
To: hp_agilent_equipment@yahoogroups.com
Date: Saturday, July 15, 2017, 11:16 PM
There might be some NOS parts somewhere but
neither Google nor eBay brings up anything for "Signalite
82R7."
Jeremy?
On Sat, Jul 15, 2017 at
7:09 PM Doug dmcgarrett@...
[hp_agilent_equipment] <hp_agilent_equipment@yahoogroups.com>
wrote:
?
On 07/15/2017 05:00 PM, Bob Goodrich bobgoodrich84@...
[hp_agilent_equipment] wrote:
> Signalite 82R7
Wonder if it's still available. That was a l o n g
time ago!
--
4.
-- With Best regards, Thomas S. Knutsen.
?Please? avoid sending? me? Word? or? PowerPoint? attachments.
|
Re: 141T reference replacement..a cure??
These tubes were designated as Z82R7. Spec sheet is at folowing link. file:///C:/Documents%20and%20Settings/Administrator/My%20Documents/Downloads/Signalite-Hivac%20neon%20regulators-LM317.pdf <<<
Who would think replacing this obsolete tube would cause such an upstir! Dennis -------------------------------------------- On Sat, 7/15/17, Jeremy Nichols jn6wfo@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote: Subject: Re: [hp_agilent_equipment] Re: 141T reference replacement..a cure?? To: hp_agilent_equipment@... Date: Saturday, July 15, 2017, 11:16 PM There might be some NOS parts somewhere but neither Google nor eBay brings up anything for "Signalite 82R7." Jeremy? On Sat, Jul 15, 2017 at 7:09 PM Doug dmcgarrett@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote: ? On 07/15/2017 05:00 PM, Bob Goodrich bobgoodrich84@... [hp_agilent_equipment] wrote: > Signalite 82R7 Wonder if it's still available. That was a l o n g time ago! -- Sent from my iPad 4.
|
Thanks Vladan, I will post a question on the Keysight forum.
Roland.
________________________________
De : hp_agilent_equipment@...
[mailto:hp_agilent_equipment@...]
Envoy¨¦ : dimanche 16 juillet 2017 23:48
? : hp_agilent_equipment@...
Objet : RE: [hp_agilent_equipment] 8594E power supply
Hi Roland,
If the boards have HP logos, I would go back to this thread on the Keysight
forum
and ask MikeM if he can provide something, even if it's just similar. There
is a very good chance that the boards for the 8593E, 94E and 95E were just
variants of the same design, so any of those schematics might be useful even
if they have different part numbers. I don't have those schematics, but I
will look in my files and double check.
Vladan
|
Hi Roland,
If the boards have HP logos, I would go back to this thread on the Keysight forum
and ask MikeM if he can provide something, even if it's just similar. There is a very good chance that the boards for the 8593E, 94E and 95E were just variants of the same design, so any of those schematics might be useful even if they have different part numbers. I don't have those schematics, but I will look in my files and double check.
Vladan
|
Hi Vladan,
No way to find the exact schematics for my 8594E spectrum analyser power
supply! It looks like this is one HP production, have you an idea where
those schematics can be found?
Thanks,
Roland F8CHK
For all of you with the 859X series portable spectrum analyzers, here is
some information that may be useful. Earlier versions of the analyzers used
a power supply which was designed and made outside of HP. After a few years,
failures started surfacing and HP (re)designed the supply in-house. The
later supplies are therefore a HP design and those are the ones for which a
schematic is often available. Those schematics will have the HP logo, etc.
in the bottom right corner.
Vladan
________________________________
Posted by: pianovt@...
________________________________
|
Re: RAM backup battery in HP 8112A
Hi David, You do need the right sort! My 8112 didn't retain settings and hadn't for the couple of years I've owned it. I finally got round to doing something about it about 8 weeks back - opened it up, read the part number off the lithium battery I found inside and ordered a replacement. As I was about to fit it a closer look revealed what looked more like a trickle charge circuit and a quick measure confirmed it was really hoping for a 2.4V Nicad so that's what I fitted! The circuit configuration seemed to match that in the 8116 manual rather than anything I found for the 8112 all of which seemed to describe Li. It has worked fine since then BTW.
All the best Adrian
On Sunday, July 16, 2017 6:55 PM, "'David C. Partridge' david.partridge@... [hp_agilent_equipment]" wrote:
?
I'm looking at an 8112A, which is fitted with a Ni-Cd battery on the
processor board, rather than a Panasonic BR-2/3AT2P 3V Lithium primary cell.
The unit has serial 2343G01456 and processor board number 08116-66523. I
think this is covered by backdating changes 29 and 41.
What it doesn't say is the type of battery - I assume just about any 3.6V
Ni-Cd that will fit?
|
Re: RAM backup battery in HP 8112A
When I removed it, I found it was a GP18AAK2A1H 2.4V NiCd. I found on pretty quickly.
D.
toggle quoted message
Show quoted text
-----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] Sent: 16 July 2017 19:19 To: hp_agilent_equipment@... Subject: Re: [hp_agilent_equipment] RAM backup battery in HP 8112A On 7/16/2017 10:55 AM, 'David C. Partridge' david.partridge@... [hp_agilent_equipment] wrote:
What it doesn't say is the type of battery - I assume just about any
3.6V Ni-Cd that will fit?
Assuming it's not going to be permanently trickle charged, rather only when it's powered up, an NiMH cordless phone battery pack would work well and they don't leak like NiCads inevitably will. Dan ------------------------------------ Posted by: Dan Rae <danrae@...> ------------------------------------ ------------------------------------ Yahoo Groups Links
|
Re: Time Interval Multimeter on HP-1725A
I have a 1742A scope (AFAIK just a 1740A plus the multimeter) with that time interval multimeter on it. The 1742A manual includes basic operating instructions for the multimeter, which is referred to as "option 034." Service information, as an earlier reply noted, is limited to the Time-Interval Decoder A17 (part of the scope), which is covered in Service Sheet 16 of the 1742A manual. I do not have the manual for the multimeter itself but, as mine works, or at least I think it does, I might be able to make tests or measurements on mine if that would help you.
Jeremy?
?
Picked up an HP-1725A at Xenia this year with a couple of known defects including a non-functional Time Interval Multimeter option. Have the scope working for the most part.?
I have so far not found anything on the operation of the Time Interval Multimeter. Which is odd as most HP stuff is well covered online. Maybe I'm just not typing the correct search terms.
Can anyone help??
Thanks
|
Re: RAM backup battery in HP 8112A
On 7/16/2017 10:55 AM, 'David C. Partridge' david.partridge@... [hp_agilent_equipment] wrote:
What it doesn't say is the type of battery - I assume just about any 3.6V
Ni-Cd that will fit?
Assuming it's not going to be permanently trickle charged, rather only when it's powered up, an NiMH cordless phone battery pack would work well and they don't leak like NiCads inevitably will. Dan
|
RAM backup battery in HP 8112A
I'm looking at an 8112A, which is fitted with a Ni-Cd battery on the
processor board, rather than a Panasonic BR-2/3AT2P 3V Lithium primary cell.
The unit has serial 2343G01456 and processor board number 08116-66523. I
think this is covered by backdating changes 29 and 41.
What it doesn't say is the type of battery - I assume just about any 3.6V
Ni-Cd that will fit?
|
Re: Anybody got a good LCR meter that they want to sell?
Dr. David Kirkby (Kirkby Microwave Ltd)
|
Re: Time Interval Multimeter on HP-1725A
On Sun, Jul 16, 2017 at 5:22 PM, W0MPM.John@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
Picked up an HP-1725A at Xenia this year with a couple of known defects including a non-functional Time Interval Multimeter option. Have the scope working for the most part.
I have so far not found anything on the operation of the Time Interval Multimeter. Which is odd as most HP stuff is well covered online. Maybe I'm just not typing the correct search terms.
Can anyone help?
the multimeter option is covered by a separate service manual, but the time interval multimeter is a standard HP-3476A (or B, afair) with a separate switch to read either its inputs or the time interval dependent voltage present on all the 17xx scopes (always, as far as I remember). So you could use the 3476 service manual and schematics to fix the multimeter. With a slide switch in the "time interval" position, it reads the 1725's time interval output, which is covered by the scope manual. HTH Frank IZ8DWF
|
Time Interval Multimeter on HP-1725A
Picked up an HP-1725A at Xenia this year with a couple of known defects including a non-functional Time Interval Multimeter option. Have the scope working for the most part.?
I have so far not found anything on the operation of the Time Interval Multimeter. Which is odd as most HP stuff is well covered online. Maybe I'm just not typing the correct search terms.
Can anyone help??
Thanks
|
Re: 141T reference replacement..a cure??
I'm afraid that radiologically enhanced neon bulbs are
pretty much a thing of the past. Once, the public viewed
the use of radioactive materials as being new and sciency.
Now, they are terrified... and the regulations are to match.
Once upon a time, I had a pair of steel enveloped reference
tubes, of this sort (really tiny, grain of rice sized) that
were hot as hell gamma wise. They were made for bomb fuses,
and were pulled from the trash by some dead relative of mine
at Diamond Ordinance and Fuse Labs in the '50s.
Tektronix scopes of the 513D era were full of glass cased,
silver covered neon like reference tubes that kick up the
geiger counter quite well.
I doubt one could economically run a production line that
made tubes like that anymore, what with the regulations
picture. The demise of the "radium girls" made that a
pretty sure thing.
-Chuck Harris
Jeremy Nichols jn6wfo@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
There might be some NOS parts somewhere but neither Google nor eBay brings
up anything for "Signalite 82R7."
Jeremy
On Sat, Jul 15, 2017 at 7:09 PM Doug dmcgarrett@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
On 07/15/2017 05:00 PM, Bob Goodrich bobgoodrich84@...
[hp_agilent_equipment] wrote:
Signalite 82R7 Wonder if it's still available. That was a l o n g time ago!
|
Re: 141T reference replacement..a cure??
They really shouldn't. The aging problem is due to
sputtering of the electrode material onto the glass
envelope. This evaporated metal travels to the glass,
and knocks gas molecules/atoms to the surface where
they get permanently stuck in the sputtered metal.
Kind of a crude vacuum pump that eliminates the
very important gas from the envelope.
-Chuck Harris
'Gary Appel' garyappel@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
Wouldn¡¯t NOS parts have the same problem from age?
Gary Appel
From: mailto:hp_agilent_equipment@...
Sent: Saturday, July 15, 2017 6:09 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Re: 141T reference replacement..a cure??
These guys claim to have a Z82R10 available for $5.95. It might be a suitable replacement.
It might require a change in the series Resistor R21.
|
Re: 141T reference replacement..a cure??
Ah! Way better than my memory! Thanks for the reference.
-Chuck Harris
Bob Goodrich bobgoodrich84@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
Below is a link to a Signalite application note pamphlet..Page 14 has the Z series of VR tubes.
www.philbrickarchive.org/jlrmsousa/signalite_glow_lamps.pdf
Bob
|
Re: HP 8566B / 8568B bus interconnect cable
I have indeed opened the connectors and inspected the connections. From what I can tell, they all look OK, although due to the density of the connections, it is hard to get a good look at the middle row. In any case, if it was due to faulty connection(s), the cable would not work with either instrument, would it?
|
Re: Replace Neon NE-2 with Zener in 141T PSU?
Most of the trouble in the PSU pcb seems to stem from overheating, due to the fact that there`s very little moving air. I used a chassis punch to make a couple of holes in the bulkheads downstream of the fan to help with this. Cheers!......Don Collie ZL4GX
?
There are two phenomena going on here.
The reason that there is a radioisotope inserted
into "neon" references, is the neon strikes at
a different voltage when exposed to light, vs dark.
This is an always thing.
The second thing that happens is the neon gas
gets buried into the glass envelop by the
sputtered electrode material trapping it against
the glass envelope. Sputtering changes the
composition, and pressure, of the gas mixture,
which changes the overall characteristics of
the tube.
So, if you have a neon voltage *reference*, it will
always have some radioactive material sintered into
the electrodes to prevent light/dark strike voltage
differences.
If the neon reference has changed its gas composition
too much to strike, for whatever reason, it will have
the wrong voltage reference value too... regardless
of what you do to make it strike.
As to whether adding light of this or that energy
will cause the neon reference to strike over, that
it happens at all is the result of the photoelectric
effect, where stray electrons are created by the
glass envelope, and the electrodes, when the photons
strike. Ultimately, it is the electrons that reduce
the strike-over voltage (see Paschen's law for
more info).
-Chuck Harris
David Wise david_wise@... [hp_agilent_equipment] wrote:
> Would you guys slow down long enough for me to type a reply? :)
>
>
> Tom, Dave,
>
>
> I wish. But the glass stops beta. The Kr-85 worked because it was inside.
>
>
> Bob, Elliott,
>
>
> So many parts in series... sometimes brute force is the best solution, but this
> one puts me off. That's just my personal taste; if you want to do it, knock
> yourself out.
>
>
> Elliott,
>
>
> HP used 1% metal film resistors. The pot is a weak point for long-term stability,
> but I think that since it's in a voltage divider the high-leg tempco compensates
> the low-leg tempco.
>
>
> In a related thread, Alan Melia suggests adding a LED to illuminate the gas tube.
> If the problem was dark effect, brought on by Kr-85 depletion, that should work
> around it just dandy. I hope someone tries it. I can't, my ZZ1000 is still
> working. If I can find a flickering neon at home, I'll try to figure out what
> wavelength LED is the most effective. It will be visible light, not UV, the glass
> blocks UV, same as external nuclear radiation.
>
>
> Dave Wise?
>
>
> ______________________________ __ From: hp_agilent_equipment@yahoogroups.com
> < hp_agilent_equipment@yahoogroups.com> on behalf of Tom Gardner tggzzz@...
> [hp_agilent_equipment] < hp_agilent_equipment@yahoogroups.com> Sent: Friday, July
> 14, 2017 2:18 PM To: hp_agilent_equipment@yahoogroups.com Subject: Re:
> [hp_agilent_equipment] Re: Replace Neon NE-2 with Zener in 141T PSU?
>
>
>
> Or to a supermarket and find the "LoSalt". Replacing part of the NaCl with KCl
> inevitably includes K40 :)
>
>
>
> On 14/07/17 22:15, Artek Manuals
> manuals@...< mailto: manuals@artekmanuals.com> [hp_agilent_equipment]
> wrote:
>
>
> Go down to one of those 2nd hand store with your geiger counter and find a very
> old $5 watch with the glow in the dark radium painted hands and dial. Peel of the
> minute hand and shrink tube it to the NE-2 :-)
>
>
> Dave manuals@...< mailto: manuals@artekmanuals.com>
>
>
>
> On 7/14/2017 5:06 PM, 'Alan Melia'
> Alan.Melia@...< mailto: Alan.Melia@btinternet.com> [hp_agilent_equipment]
> wrote:
>
>
> ?
>
> The thing is that most "zeners" do not depend on the Zener effect. That only
> occurs around voltages up to around 4volts, above 5v the process is Avalanche
> Breakdown , a bit like a gas tube. Then the temperature coefficient of these two
> processes have opposite senses so if you combine a true Zener with a forward diode
> or an avalanche diode you can minimise the tempco. The lowest tempcos are usually
> around 5 to 6v."zeners".
>
> Alan G3NYK ----- Original Message ----- From: Bob Albert bob91343@...
> [hp_agilent_equipment] bob91343@...%20[hp_ agilent_equipment]> To:
> hp_agilent_equipment@yahoogroups.comhp_ agilent_equipment@yahoogroups. com>
> Sent: Friday, July 14, 2017 9:16 PM Subject: Re: [hp_agilent_equipment] Re:
> Replace Neon NE-2 with Zener in 141T PSU?
>
> Actually I think the lowest temperature coefficient is around 5V for zener diodes.
> The 6.2 V units are very stable also so you don't need as many of those.
>
> When you put zeners in series you invoke the concern of impedance. Low voltage
> zeners have a fairly high impedance compared to just a few higher voltage ones.
> So if the current through it changes, so will the voltage.
>
> There are more elegant solutions to this 'problem' but the whole thread is
> probably more trouble than it's worth.
>
> Let us know your re sults.
>
> Bob
>
>
> On Friday, July 14, 2017 1:00 PM, "w7qed@...
> [hp_agilent_equipment]"< mailto: w7qed@...[hp_ agilent_equipment]>
> < hp_agilent_equipment@yahoogroups.com>hp_ agilent_equipment@yahoogroups. com>
> wrote:
>
>
>
>
> Hi Dave,
>
> In theory, ~18x 4.5v zeners would provide the lowest drift reference for a
> pure-zener design.
>
> However, a single 82v zener has a tempo of around 0.073%. Compared to the 0.004%
> of the original reference bulb this is pathetic, however, looking at the dozens of
> carbon resistors, dried out caps, and of course the potentiometer that sets the
> gain (and remember, new pots are generally not better than 100 PPM unless they are
> very expensive), I think the drift and tempo from a single zener will be the least
> of this circuit's problems!
>
> Thanks all for your input!
>
> --E W6EL
>
>
>
>
>
>
>
> -- Dave Manuals@...< mailto: Manuals@ArtekManuals.com>
> <>
>
> [ https://ipmcdn.avast.com/images/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif]<>
> Virus-free.
> <>
>
>
>
>
>
|
Re: Anybody got a good LCR meter that they want to sell?
I agree!
The ultracheap testers are all based on this (AFAIK)
Given its price it is an amazing little gadget. Not just LCR, but measures and identifies transistors and FET's.
No it's not a precision instrument but a very very hand gadget in the toolbox.
/Lasse
16 juli 2017 00:20:30 +02:00, skrev 'Dr. David Kirkby (Kirkby Microwave Ltd)' drkirkby@... [hp_agilent_equipment] :
|
Re: 141T reference replacement..a cure??
Wouldn¡¯t NOS parts have the same problem from age?
?
Gary Appel
toggle quoted message
Show quoted text
Sent: Saturday, July 15, 2017 6:09 PM
Subject: Re: [hp_agilent_equipment] Re: 141T reference
replacement..a cure??
?
?
These guys claim to have a
Z82R10? available for $5.95. It might be a suitable replacement.
It might require a change in the
series Resistor?? R21.
?
?
|
David C. Partridge
Jeremy Nichols
John W0MPM