Plus they were side-loaded, not being pulled straight out. That leverage counts for a lot. ?
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From: [email protected] <[email protected]> On Behalf Of Lothar baier
Sent: Friday, February 25, 2022 3:14 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles? Yep the screws are metric on top of it which means they have a finer pitch which is better to handle pull , if I remember they were either M6 or M8 screws , doing some quick calculations you would need about 127lbs of force to rip a correctly formed M8 out of a Die cast frame , the 8753 weighs about 75lbs ? Sent from for Windows ? ? The straps are mounted with quite sturdy screws into the frame side rails, and the plastic is just a cover for a stainless steel strap that is held by those screws. I have handled a lot of HPAK TE over the years and never had a strap fail.
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Rich Miller via groups.io
Sent: Friday, February 25, 2022 2:48 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth.
Rich
> On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
>
> ?I smell a small amount OCD. But kidding aside, *beautiful* kit!
>
> I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
>
> For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
>
> Wilko
>
>
>
>
>
>
>
?
|
Re: How can I measure the bandwidth of an audio transformer with the HP8903B ?
Thanks Tom for clarifying that the inductance of the transformer is predominant over the parasitic inductance of the resistors.
-- Cheers
? ? Attilio
|
Bottom line is that with the weight of the 8753 there is no conceivable way the strap can fail ,? I fixed and handled hundrets of 8753 and other instruments at tucker and don’t remember ever a strap breaking , same goes for the PNA and
8753 units we used at nokia
?
Sent from for Windows
?
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From: 搁别苍é别 via groups.io
Sent: Friday, February 25, 2022 2:20 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
?
and do not forget it is and angled force pull and a screw on either end ...so divide by 2. So it is a combination of pull and shear.
搁别苍é别
On 2/25/22 12:13 PM, Lothar baier wrote:
Yep the screws are metric on top of it which means they have a finer pitch which is better to handle pull , if I remember they were either M6 or M8 screws , doing some quick calculations you would need about 127lbs of force to rip a correctly
formed M8 out of a Die cast frame , the 8753 weighs about 75lbs
?
Sent from for Windows
?
?
The straps are mounted with quite sturdy screws into the frame side rails, and the plastic is just a cover for a stainless steel strap that is held by those screws. I have handled a lot of HPAK TE over the years
and never had a strap fail.
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of Rich Miller via groups.io
Sent: Friday, February 25, 2022 2:48 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth.
Rich
> On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
>
> ?I smell a small amount OCD. But kidding aside, *beautiful* kit!
>
> I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
>
> For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
>
> Wilko
>
>
>
>
>
>
>
?
?
|
and do not forget it
is and angled force pull and a screw on either end ...so divide
by 2. So it is a combination of pull and shear.
搁别苍é别
On 2/25/22 12:13 PM, Lothar baier
wrote:
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Show quoted text
Yep the screws are metric on top of it
which means they have a finer pitch which is better to handle
pull , if I remember they were either M6 or M8 screws , doing
some quick calculations you would need about 127lbs of force
to rip a correctly formed M8 out of a Die cast frame , the
8753 weighs about 75lbs
?
Sent from for Windows
?
?
The straps are
mounted with quite sturdy screws into the frame side rails,
and the plastic is just a cover for a stainless steel strap
that is held by those screws. I have handled a lot of HPAK TE
over the years and never had a strap fail.
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of
Rich Miller via groups.io
Sent: Friday, February 25, 2022 2:48 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E
Handles
Actually - My instrument came with no front handles, and I do
not trust the straps when carrying this behemoth.
Rich
> On Feb 25, 2022, at 12:36 PM, Wilko Bulte
<wkb@...> wrote:
>
> ?I smell a small amount OCD. But kidding aside,
*beautiful* kit!
>
> I too want my equipment as clean as possible. Which, eg
for the 5342a took quite a bit of time to assemble the
cosmetically best parts into my shack unit. The 2nd best
looking 5342a is on loan to a ham friend, #3 is incomplete and
lives in the cellar.
>
> For those in EU, I have 2 sets of HP handles available,
ex-HP 8642a, for sale/trade.
>
> Wilko
>
>
>
>
>
>
>
?
|
Yep the screws are metric on top of it which means they have a finer pitch which is better to handle pull , if I remember they were either M6 or M8 screws , doing some quick calculations you would need about 127lbs of force to rip a correctly
formed M8 out of a Die cast frame , the 8753 weighs about 75lbs
?
Sent from for Windows
?
toggle quoted message
Show quoted text
From: n8zmTWH via groups.io
Sent: Friday, February 25, 2022 2:10 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
?
The straps are mounted with quite sturdy screws into the frame side rails, and the plastic is just a cover for a stainless steel strap that is held by those screws. I have handled a lot of HPAK TE over the years
and never had a strap fail.
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Rich Miller via groups.io
Sent: Friday, February 25, 2022 2:48 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth.
Rich
> On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
>
> ?I smell a small amount OCD. But kidding aside, *beautiful* kit!
>
> I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
>
> For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
>
> Wilko
>
>
>
>
>
>
>
?
|
The straps are mounted with quite sturdy screws into the frame side rails, and the plastic is just a cover for a stainless steel strap that is held by those screws. I have handled a lot of HPAK TE over the years and never had a strap fail.
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Rich Miller via groups.io Sent: Friday, February 25, 2022 2:48 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth. Rich On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
?I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
|
The front handles can handle the weight but not impact if units ate poorly packed , as far as the side straps concerns I have never seen one of them giving in ,? not sure if you ever have taken a closer look on how they are constructed
but its actually a stainless steel strap that is screwed with M6 Screws to the frame , so unless you rip out the threats there isn’t really a failure mode under normal conditions where the strap can break
?
Sent from for Windows
?
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From: Rich Miller via groups.io
Sent: Friday, February 25, 2022 1:49 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
?
I would never ship it with the front handles on, I would have thought the handles would be more robust than these side straps. I have no confidence in them handling the weight.?
Rich
On Feb 25, 2022, at 12:42 PM, Lothar baier <Lothar@...> wrote:
?
Unless you find a new set the handles are fairly hard to come by ,? most companies removed them to avoid people trying to lift the units of benches using the front handles and as a result either dropping and damaging the unit and/or hurting
themselves for the units that entered the used equipment market with handles the handles usually get bent up when the units were shipped and subsequently were removed by dealers ,? I fixed and calibrated hundrets of 8753D, E,ES units when I worked at tucker
and 90% of the units that came in the lab either came in with no handles or the handles were bad
?
Sent from for Windows
?
?
I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
?
|
Actually, I am not even worried about the color - I posted why I want them a few moments ago. You are right, virtually no handles available. I did buy some for a Marconi instrument I had, but weight was of no concern. Marconi handles seem to be everywhere!
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On Feb 25, 2022, at 10:50 AM, nj902 <wb0emu@...> wrote:
?"Why do you want the handles?? The instrument will work fine without them." I'm not that guy!.? I love the appearance of the instruments with handles!? True, some people don't care about appearance, but these instruments were very expensive.? Sitting in front of it, the only thing that separates you from when it was 20, 30, 40 or more thousand $ is a little time.? It's no different than a used car.? "Why wash it?? It's not new" I try to make every instrument I get look it's best.? I clean off any stickers, touch up any scratches, clean off any grunge on the paint.? I hope you do to! Be aware that HP / Agilent used the same handle design for many years so there are at least three different color combinations.? You can see some of the minor differences in this picture of my RF bench.? For example - my 8753ES is from Agilent, but the S-parameter test set is an HP so the handle (and instrument) colors aren't the same.? There should be plenty of the handles on that auction site.? Other people must love them too because they're usually expensive.
|
The problem is that the 8753 as you already noticed is heavy ,? when you have a unit is on a bench riser or in a rack people underestimate the weight they pull it out and then the unit drops
?
Sent from for Windows
?
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From: Rich Miller via groups.io
Sent: Friday, February 25, 2022 1:48 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
?
Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth.
Rich
> On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
>
> ?I smell a small amount OCD. But kidding aside, *beautiful* kit!
>
> I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
>
> For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
>
> Wilko
>
>
>
>
>
>
>
?
|
I would never ship it with the front handles on, I would have thought the handles would be more robust than these side straps. I have no confidence in them handling the weight.?
toggle quoted message
Show quoted text
On Feb 25, 2022, at 12:42 PM, Lothar baier <Lothar@...> wrote:
?
Unless you find a new set the handles are fairly hard to come by ,? most companies removed them to avoid people trying to lift the units of benches using the front handles and as a result either dropping and damaging the unit and/or hurting
themselves for the units that entered the used equipment market with handles the handles usually get bent up when the units were shipped and subsequently were removed by dealers ,? I fixed and calibrated hundrets of 8753D, E,ES units when I worked at tucker
and 90% of the units that came in the lab either came in with no handles or the handles were bad
?
Sent from for Windows
?
?
I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
?
|
Actually - My instrument came with no front handles, and I do not trust the straps when carrying this behemoth.
Rich
toggle quoted message
Show quoted text
On Feb 25, 2022, at 12:36 PM, Wilko Bulte <wkb@...> wrote:
?I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
|
Re: HP 1727A CRO: Problem with the vertical output amplifier.
There is also no ripple on any of the voltage rails or voltage drop between U1 and U2.
Yesterday I did remove the whole board and clean U1 and U2 with isopropyl alcohol, I wanted to avoid oily things.
|
Re: HP 1727A CRO: Problem with the vertical output amplifier.
I appear to have misreported some things...
I can get pins 5&7 of U2 to be exactly the same with the balance control(R23), then on U2 pin 2 I get 42.30V and on pin 3 I get 41.81V, that is still a difference of half a volt give or take a millivolt or two, is this what causes the distortion?
|
Re: How can I measure the bandwidth of an audio transformer with the HP8903B ?
Whoever cited parasitic inductance of resistors as something to
worry about in this case is worrying way too much! The transformer
will of course dominate by orders of magnitude.
-- Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 2/25/2022 10:00, Jim Adney wrote:
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I just measured a very large (~3/4" x 7") 3 Ohm Ohmite Brown
Devil. It measues ~3 Ohms and ~5 uH. My inductance meter is quite
cheap, but I don't think it's off by a factor of 10,000.
|
Re: How can I measure the bandwidth of an audio transformer with the HP8903B ?
I just measured a very large (~3/4" x 7") 3 Ohm Ohmite Brown Devil. It measues ~3 Ohms and ~5 uH. My inductance meter is quite cheap, but I don't think it's off by a factor of 10,000.
|
Unless you find a new set the handles are fairly hard to come by ,? most companies removed them to avoid people trying to lift the units of benches using the front handles and as a result either dropping and damaging the unit and/or hurting
themselves for the units that entered the used equipment market with handles the handles usually get bent up when the units were shipped and subsequently were removed by dealers ,? I fixed and calibrated hundrets of 8753D, E,ES units when I worked at tucker
and 90% of the units that came in the lab either came in with no handles or the handles were bad
?
Sent from for Windows
?
toggle quoted message
Show quoted text
From: Wilko Bulte via groups.io
Sent: Friday, February 25, 2022 11:36 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] WTB HP-8753E Handles
?
I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
?
|
I smell a small amount OCD. But kidding aside, *beautiful* kit!
I too want my equipment as clean as possible. Which, eg for the 5342a took quite a bit of time to assemble the cosmetically best parts into my shack unit. The 2nd best looking 5342a is on loan to a ham friend, #3 is incomplete and lives in the cellar.
For those in EU, I have 2 sets of HP handles available, ex-HP 8642a, for sale/trade.
Wilko
|
Re: HP 1727A CRO: Problem with the vertical output amplifier.
On Thu, Feb 24, 2022 at 11:42 AM, Alex_03 wrote:
The input signal for the captures was not the calibrator, it was an external function generator. I chose triangle because it makes it easiest to see the distortion on the screen, sine shows it too and obviously square does not, hence the external function generator.
I completely forgot that I had my scope in AC coupling for those captures. new ones are attached along with pics of both sine and triangle on the screen, which I just realized I never attached to my original post, oops.
Attached in order of pins 3/6, 4/5, and 12/13 of U1(hopefully). I also captured the final vertical output(AC coupled so you can actually see something).
----------- The measurement that is most puzzling is pin 7 of U2 (=pin 13 of U1) is at 27.77V, pin 5 of U2 (=pin 12 of U1) is at 27.5V but pins 2&3 of U2 are nicely balanced at 42V. If internals of U2 is exactly like the figure, 270mV difference across the input transistors should steer the current completely to pin 2 which should cause different voltages at pin 2 and pin 3 of U2.? With zero input could you re-measure pins 12&13 of U1 and pins 2&3 of U2? Possible scenarios: 1) 165-ohm terminations at the other side of the plates drifted and not balanced anymore. 2) Look at 53.3VF supply for ripple and DC voltage while you are feeding in the signal.? 3) There may be a large voltage drop from pins 12/13 of U1 to pins 5&7 of U2, and in reality voltage at pins 5&7 of U2 could be closer at the IC terminals. If you measure DC voltages touching the IC pins vs touching components (e.g. R24/R25) do you see a difference? You may try carefully removing U1 and reseating it. Removing, cleaning terminals of U2 and reseating is also a good idea but it is trickier so you have to decide whether you are comfortable with it after reading the service manual. I recommend focusing on why pins 5&7 of U2 are 270mV apart but pins 2&3 of U2 match to the same voltage.? As you also wrote this is not a push-pull stage so there is no NPN/PNP cross over. Also U2 has cascoding inside but its function is beyond a simple cascode, it is built as a transimpedance amplifier.? Ozan
|
Re: Off Topic : Admiralty B40 Receiver
On Friday 25 February 2022 11:44:46 am Harold Foster wrote: I would also highly recommend the site:
especially the forums. Seconded! I'm not currently active in there, but have been in the past... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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Re: Off Topic : Admiralty B40 Receiver
I would also highly recommend the site:
especially the forums.
Hal
|
Attilio
Alex_03
Harold Foster