Re: Placing Shelf on Casters for HP Equipment
"Dave McGuire" <mcguire@...> writes: If I understand what you're saying correctly, these do in fact work
for units mounted atop one another, in vertically adjacent rack units,
without wasting 1U of space. They are a lot more than 1/32" thick. (I
have a few of these in service) There's a useful post about using angle irons for support rails on EEVBlog (also discusses other aspects of rack mounting): My confusion was that if modules mounted within a rack are designed to be some whole number of units high minus 1/32" then to not take up 1U of space the support would need to be no thicker than this. But, I think the resolution is that while the front bezel is nU-1/32, the height of the rest of the unit (top to bottom cover) is less than this and leaves space for thicker supports. Did you make your own supports from angle irons, Dave? It sounds like getting 1.5 in sq angle irons 1/8" thick and then drilling custom holes for mounting to the rack could work well here. I expect the trick is drilling the holes at just the vertical height so that the modules sit on the angle iron but the flanges still mount to the front panel. Or, maybe slotted angles are good enough and customizing an angle iron without slots isn't necessary. Matt
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Re: Placing Shelf on Casters for HP Equipment
Hi Matt Regarding rack side shelves / supports ? The ones I directed you to are slides so too expensive and over the top the ones you want are as in picture My one question to you is what depth of rack are you going for as I ?would think 600 mm would be deep enough for you as the without a back door equipment / cables ?can stick out of the back If I am wrong then I am positive others will correct me ? I believe you ask about U spacing? ? I do not generally use rack side shelves / supports for every 1 u unit unless they have to come out regularly then normally on the expensive slides Plus you cannot pack a 19 inch rack 100 % ?and that is a different subject if a unit has vent holes on the top you require 1 U space above or sometimes a fan tray ? Assuming we have 2 U that is 2? x 1.75 inch =3.5 inch or 88.91 mm The actual 2U test equipment might measures ?????86.2 mm to 88.4 mm so making things tight as the support is normally 1.85 mm thick There is a curtain amount of slack in the build and some unites have a larger front panel than the unit for cooling so I general start at the bottom of the rack with 1 U blank then 2U of power or 2 U blank If I require a bit more space then we have a patch panel that is not quite 2 U ?or a vent / blank Panel that is not quite 2 U ? Regards Paul
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Re: Placing Shelf on Casters for HP Equipment
Thanks, Michael.? ?Always interesting to hear how people have obtained equipment, on-topic or not.? ? ? ? Jim
Sent from my Verizon, Samsung Galaxy smartphone
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-------- Original message -------- From: "Michael A. Terrell" <terrell.michael.a@...> Date: 11/8/21 9:36 AM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment
Yes, it was 'Point Of Sale' hardware. I bought both minicomputers, ten in counter LASER scanners along with 14 cash registers and 14 printers. Two complete systems, from two stores..They threw in two chargers and an electric pallet jack, all for $100. I scraped the scanners for the LASER tubes and power supplies. I sold them for $400, and I got about $75 for the machined aluminum housings. The profits went to more equipment for the shop, at the Orlando Hamfest.
I take it POS stands for Point Of Sale, not Piece Of S***.? When I was in engineering school in the 1980s, we used the DEC Pro 350 computers, and they actually had an operating system called pOS!? Not a well thought out name!? ? ? ?Jim Ford?
Sent from my Verizon, Samsung Galaxy smartphone
-------- Original message -------- Date: 11/8/21 12:33 AM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment
There are also 23" wide racks that came from the Telco industry.
I have two, dual sized enclosed racks They are 19", but you can remove the doors and side panels, then turn it 90 degrees to use it as a 23" rack.
They are from some long gone National Semiconductor Datachecker POS systems that were scrapped 25 years ago. On Sun, Nov 7, 2021 at 10:31 PM Dave McGuire < mcguire@...> wrote: On 11/7/21 8:38 PM, Matt Huszagh wrote:
> I googled "HP test equipment rack" and the 19" rack popped up. I have
> seen these before, though I didn't know the term (or know that it was a
> standard). I also did not know that these are what HP, Agilent and
> Keysight use for their test equipment racks.
? ?Well, they followed the 19" rack standard.? Just like all of the
computer manufacturers (HP included) followed it too.
? ?The vernacular: One "rack U" (rack unit) is 1.75".? A "1U"
rack-mounted device is 1.75" tall, a "2U" chassis is 3.5", etc.? About
95% of the hardware you'll run across, test equipment and server-class
computers alike, is sized in these increments.? Soon you'll be able to
recognize them on sight and plan out your rack space allocations: "Oh, I
see that HP 3325A is a 3U box".? "Ah, I can put a 1U file server right
here".
? ?Look for a picture of the front one of these racks, empty, and look
at the holes facing you on the left and right.? Notice the spacing
pattern of the holes.? It looks irregular, but if you stare at it for a
moment you'll see that they're spaced out for 1.75" increments.
? ?All of this works amazingly well, and you will love it.
? ?This isn't just test equipment stuff.? If you haven't ever seen a
datacenter in person, surely you've seen pictures of them.? Those are
the same racks.
? ?Keyboardless synthesizers, signal processors, and amplifiers in
recording studios and on on concert stages...same racks.
? ?AT&T came up with this standard for telephony equipment in
1922...Yes, 99 years ago.
> I'm not sure if this is a good excuse but I'm relatively young (< 30)
> and only been doing electronics for the last couple years, when I
> started teaching myself. I also don't come from an engineering
> background, so I've probably missed some things that are evident to
> others in the field. I did study physics undergrad though, and research
> is one of the places I've come across these. But, none of us were too
> concerned that these were called 19" racks.
? ?It's not a good excuse. ;)? But it's never too late to catch up, and
you can fill in all of the knowledge blanks here.
? ? ? ? ? ? -Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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Re: Placing Shelf on Casters for HP Equipment
Why would you put a rack behind a four foot deep workbench? Even behind three feet deep would be a lot of stretching when you're disabled.
On Mon, Nov 8, 2021 at 3:41 PM Bruce < bruce@...> wrote: What do you do with the lower rack space on racks standing behind the?
benches ?
Cheers!
Bruce
Quoting "Michael A. Terrell" <terrell.michael.a@...>:
> Some of the racks are free standing, and others are beside the bench. My
> workshop is 1200 square feet, in a stand alone garage.
>
> On Mon, Nov 8, 2021 at 3:17 PM Bruce <bruce@...> wrote:
>
>> Interesting idea - but if the rack is behind a bench, the drawers are
>> a bit difficult to get to.? Much depends on how yu position the
>> equipment "racking" relative to the work space.
>>
>> Cheers!
>>
>> Bruce
>>
>> Quoting "Michael A. Terrell" <terrell.michael.a@...>:
>>
>> > I collected turntable drawers from old school intercom systems. With a
>> > little work, I turned them into drawers to go in the lower part of racks
>> to
>> > store cables and small equipment.
>> >
>> > On Mon, Nov 8, 2021 at 3:05 PM Bruce <bruce@...> wrote:
>> >
>> >> One disadvantage to racks is that it is difficult to utilize the space
>> >> below bench level.? If you look at HP packaged configurations (HP
>> >> 8510C for example) does not have front panel control or is controlled
>> >> ia GPIB.
>> >>
>> >> True, things like power supplies can be used on the lower level, but
>> >> generally bench top access is required for test equipment - GPIB
>> >> control is an option but commercial software is expensive and
>> >> configuration management can be complicated.
>> >>
>> >> Cheers
>> >>
>> >> Bruce
>> >>
>> >>
>> >>
>> >> Quoting Dave McGuire <mcguire@...>:
>> >>
>> >> > On 11/7/21 9:53 PM, Jim Ford wrote:
>> >> >> HP gear does have handles and rack ears that work together, at
>> >> >> least the 8566 spec an and 8530 sweep oscillator.? Handy to keep
>> >> >> the handles on there, should rearrangement be necessary.
>> >> >
>> >> >? ?The HP System I (example: 8640B) chassis system has handles built
>> >> > into the side frame castings, and ears that work with them.? The
>> >> > System II (example: 8566, 8350) chassis systems have ears that work
>> >> > standalone, and ears that work with handles.
>> >> >
>> >> >? ? ? ? ? ? ?-Dave
>> >> >
>> >> > --
>> >> > Dave McGuire, AK4HZ
>> >> > New Kensington, PA
>> >> >
>> >> >
>> >> >
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >
>> >
>> >
>>
>>
>>
>>
>>
>>
>>
>>
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>
>
>
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You can convert the 200CD to 240 volt operation by changing the transformer primaries from parallel to series as described in the manual. The -172 volts at R40 is a little higher than the -155 quoted in the manual but that shouldn't make much difference to its operation. At -172V the power dissipated in R30/31 works out at about 10 watts each if they are 3100 ohms so they need to be rated appropriately.?
Where are you in Australia?
Morris
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Re: OT: Standalone programmer for PIC17C44 (PLCC44)
I use a Picstart Plus (serial) with a homebrew PLCC adaptor. The adaptor is just a ZIF PLCC socket on a bit of isolated pad through hole protoboard with two 20 way 0.1" pin headers to go into the DIL ZF on the PicStart. 40 bits of wire wrap type 30 gauge wire connect the pins.?
You can buy a non-zif on on ebay for a coupl of pounds but check the pinning.
Robert G8RPI.? ?
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Re: Placing Shelf on Casters for HP Equipment
I agree. I have two benches with offset overhead shelves arranged in a "L" with a 45" splice (computer lives on the splice). Behind each bench is another bench with a lower (almost flor level) shelf (for equipment not currently in use). This arrangement gives me plenty of working equipment space, storage space and good "movable" work space. Had the benches custom designed and have had them at 3 different locations - they knock down for "easey" movability and are probably strong enough to put a volkswagen on. Cheers! Bruce Quoting Paul Bicknell <admin@...>:
Hi Bruce good to hear from you
Agreed about the levels below bench level assuming you have the work bench in front of the racks
But if the rack is to the side of the bench pointing into the operator either at 45 or 90 degrees the all the rack is useable
If all the deep equipment goes into a 600 mm rack and leaving the bench for the work
Just another way to skin the cat Regards Paul
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Bruce
Sent: 08 November 2021 20:06
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment
One disadvantage to racks is that it is difficult to utilize the space below bench level. If you look at HP packaged configurations (HP 8510C for example) does not have front panel control or is controlled ia GPIB.
True, things like power supplies can be used on the lower level, but generally bench top access is required for test equipment - GPIB control is an option but commercial software is expensive and configuration management can be complicated.
Cheers
Bruce
Quoting Dave McGuire <mcguire@...>:
On 11/7/21 9:53 PM, Jim Ford wrote:
HP gear does have handles and rack ears that work together, at least
the 8566 spec an and 8530 sweep oscillator. Handy to keep the
handles on there, should rearrangement be necessary. The HP System I (example: 8640B) chassis system has handles built
into the side frame castings, and ears that work with them. The
System II (example: 8566, 8350) chassis systems have ears that work
standalone, and ears that work with handles.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
Hi Bruce good to hear from you
Agreed about the levels below bench level assuming you have the work bench in front of the racks
But if the rack is to the side of the bench pointing into the operator either at 45 or 90 degrees the all the rack is useable
If all the deep equipment goes into a 600 mm rack and leaving the bench for the work
Just another way to skin the cat Regards Paul
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Bruce Sent: 08 November 2021 20:06 To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment One disadvantage to racks is that it is difficult to utilize the space below bench level. If you look at HP packaged configurations (HP 8510C for example) does not have front panel control or is controlled ia GPIB. True, things like power supplies can be used on the lower level, but generally bench top access is required for test equipment - GPIB control is an option but commercial software is expensive and configuration management can be complicated. Cheers Bruce Quoting Dave McGuire <mcguire@...>: On 11/7/21 9:53 PM, Jim Ford wrote:
HP gear does have handles and rack ears that work together, at least
the 8566 spec an and 8530 sweep oscillator. Handy to keep the
handles on there, should rearrangement be necessary. The HP System I (example: 8640B) chassis system has handles built
into the side frame castings, and ears that work with them. The
System II (example: 8566, 8350) chassis systems have ears that work
standalone, and ears that work with handles.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
Absolutely agree !
Quoting Dave McGuire <mcguire@...>:
toggle quoted message
Show quoted text
On 11/8/21 3:17 PM, Bruce wrote:
Interesting idea - but if the rack is behind a bench, the drawers are a bit difficult to get to.? Much depends on how yu position the equipment "racking" relative to the work space. With anything...tables, racks, shelves, etc, it helps to design the lab around them. My main RF bench is a large table with commonly-used lots-of-front-panel-access instruments on top of it, pushed way back, and there are two tall racks to the left and right of that bench. I've arranged instruments according to mounting requirements (weight), amount of front panel interaction is involved in their use, and grouping/relevancy.
If you set things up to use one or more racks (or any other specific type of table/shelves/etc) from the get-go, you end up with a much more usable arrangement.
Anything complex does benefit from some planning.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
What do you do with the lower rack space on racks standing behind the benches ?
Cheers!
Bruce
Quoting "Michael A. Terrell" <terrell.michael.a@...>:
toggle quoted message
Show quoted text
Some of the racks are free standing, and others are beside the bench. My
workshop is 1200 square feet, in a stand alone garage.
On Mon, Nov 8, 2021 at 3:17 PM Bruce <bruce@...> wrote:
Interesting idea - but if the rack is behind a bench, the drawers are
a bit difficult to get to. Much depends on how yu position the
equipment "racking" relative to the work space.
Cheers!
Bruce
Quoting "Michael A. Terrell" <terrell.michael.a@...>:
I collected turntable drawers from old school intercom systems. With a
little work, I turned them into drawers to go in the lower part of racks to
store cables and small equipment.
On Mon, Nov 8, 2021 at 3:05 PM Bruce <bruce@...> wrote:
One disadvantage to racks is that it is difficult to utilize the space
below bench level. If you look at HP packaged configurations (HP
8510C for example) does not have front panel control or is controlled
ia GPIB.
True, things like power supplies can be used on the lower level, but
generally bench top access is required for test equipment - GPIB
control is an option but commercial software is expensive and
configuration management can be complicated.
Cheers
Bruce
Quoting Dave McGuire <mcguire@...>:
On 11/7/21 9:53 PM, Jim Ford wrote:
HP gear does have handles and rack ears that work together, at
least the 8566 spec an and 8530 sweep oscillator. Handy to keep
the handles on there, should rearrangement be necessary. The HP System I (example: 8640B) chassis system has handles built
into the side frame castings, and ears that work with them. The
System II (example: 8566, 8350) chassis systems have ears that work
standalone, and ears that work with handles.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
On 11/8/21 3:17 PM, Bruce wrote: Interesting idea - but if the rack is behind a bench, the drawers are a bit difficult to get to.? Much depends on how yu position the equipment "racking" relative to the work space. With anything...tables, racks, shelves, etc, it helps to design the lab around them. My main RF bench is a large table with commonly-used lots-of-front-panel-access instruments on top of it, pushed way back, and there are two tall racks to the left and right of that bench. I've arranged instruments according to mounting requirements (weight), amount of front panel interaction is involved in their use, and grouping/relevancy. If you set things up to use one or more racks (or any other specific type of table/shelves/etc) from the get-go, you end up with a much more usable arrangement. Anything complex does benefit from some planning. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
On 11/8/21 3:05 PM, Bruce wrote: One disadvantage to racks is that it is difficult to utilize the space below bench level.? If you look at HP packaged configurations (HP 8510C for example) does not have front panel control or is controlled ia GPIB.
True, things like power supplies can be used on the lower level, but generally bench top access is required for test equipment - GPIB control is an option but commercial software is expensive and configuration management can be complicated. This is true, but in any working arrangement there are always things that can be put in the lower areas of a rack. You mentioned power supplies. My lab central UPS isn't rack-mount per se, but it sits in the bottom 1.5 feet of my RF sources rack. Sitting atop that is a configurable AC source, which weighs about 80lbs and doesn't involve much front panel interaction to use. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Placing Shelf on Casters for HP Equipment
Some of the racks are free standing, and others are beside the bench. My workshop is 1200 square feet, in a stand alone garage.
On Mon, Nov 8, 2021 at 3:17 PM Bruce < bruce@...> wrote: Interesting idea - but if the rack is behind a bench, the drawers are?
a bit difficult to get to.? Much depends on how yu position the?
equipment "racking" relative to the work space.
Cheers!
Bruce
Quoting "Michael A. Terrell" <terrell.michael.a@...>:
> I collected turntable drawers from old school intercom systems. With a
> little work, I turned them into drawers to go in the lower part of racks to
> store cables and small equipment.
>
> On Mon, Nov 8, 2021 at 3:05 PM Bruce <bruce@...> wrote:
>
>> One disadvantage to racks is that it is difficult to utilize the space
>> below bench level.? If you look at HP packaged configurations (HP
>> 8510C for example) does not have front panel control or is controlled
>> ia GPIB.
>>
>> True, things like power supplies can be used on the lower level, but
>> generally bench top access is required for test equipment - GPIB
>> control is an option but commercial software is expensive and
>> configuration management can be complicated.
>>
>> Cheers
>>
>> Bruce
>>
>>
>>
>> Quoting Dave McGuire <mcguire@...>:
>>
>> > On 11/7/21 9:53 PM, Jim Ford wrote:
>> >> HP gear does have handles and rack ears that work together, at
>> >> least the 8566 spec an and 8530 sweep oscillator.? Handy to keep
>> >> the handles on there, should rearrangement be necessary.
>> >
>> >? ?The HP System I (example: 8640B) chassis system has handles built
>> > into the side frame castings, and ears that work with them.? The
>> > System II (example: 8566, 8350) chassis systems have ears that work
>> > standalone, and ears that work with handles.
>> >
>> >? ? ? ? ? ? ?-Dave
>> >
>> > --
>> > Dave McGuire, AK4HZ
>> > New Kensington, PA
>> >
>> >
>> >
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
|
Re: Placing Shelf on Casters for HP Equipment
On 11/8/21 3:11 PM, Matt Huszagh wrote: Also, on further thought these may not work because the supporting
portion of the angle will presumably need to sit exactly between each
1.75" unit. I'd also imagine they need to be 1/32" thick (since this is
how much shorter each module is than the number of rack units it takes
up). But, this seems to be a bit thin to be supportive. So, I'm confused
again. If I understand what you're saying correctly, these do in fact work for units mounted atop one another, in vertically adjacent rack units, without wasting 1U of space. They are a lot more than 1/32" thick. (I have a few of these in service) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Question: XY (XYZ or Vector) instrument CRT, replacement with an LCD ?
That should be +100v in, 0v, -100v in. Or in the schematic?+50mV, 0v, -50mV.? ? ?50mV x 50.02 = 2.501V added to the 2.5V offset = 5.001V depending on the accuracy of the resistor, offsets, etc R2 calibrates the gain for the shunt.
I like the AD623A differential amplifier?because it takes differential inputs and I can set the output to be 2.5v for 0v in.? Now?+5v out represents max positive input (say?+10V), 2.5v out represents 0v input, and 0v out represents max negative input (-100V). This scales the input to fit the 5 volt range of the ADC on a PIC. Adjust according to the ADC you are using. The schematic shows an application looking at a shunt in a 12v battery path and the output goes to a PIC ADC to read positive or negative current. R is the shunt. S2 is used to short the input to zero the amplifier with R7, it must be DPDT or you might be fighting the shunt for 10 amps. The 5v supply needs to be stable,?use?a precision?regulator with 5.000v out.. Peter??
Look at the schematics, the step amplifier for example. It shows 2v/div for the steps. Connect an instrument amplifier to the Steps Out and adjust the gain. The deflection amplifiers are trickier but can be done with an instrumentation amplifier with proper scaling and offsets. You will need to protect the circuit from the 100 volt signals. Good luck with the readout lamps for the ranges, but it is possible.? Peter
hi,
Just to pull the conversation back to the?? *electronics*? of the replacement of a XYZ CRT with an LCD ??
???? { rather than the programming or software, for now }.
Does anyone have any technical expertise with? "picking off" ? the vector type (non-raster) CRT XYZ signals? (presumably from the low voltage deflection amplifiers)? ?
Assuming that somewhere in the deflection amplifier signal chain, there might be some low voltage +/- 5V signals that could be used
? --- so that could then be fed into an LCD module ( such as the $55? STM32F746G-DISCO module ?).
For this project question, the CRT display is a simple XYZ vector display, not a raster CRT:
The NewScope modules are too expensive to consider,
and this CRT issue is not concerned with longevity nor with hypothetical future replacements of the LCD with another LCD, etc.
Nor with the use of yet another CRT.
The point being that the STM LCD module may represent the possibility of actually capturing the data from, say a Tek 576 Curve Tracer( as an example), that would allow such data to be imported into a laptop for data manipulation, comparison? and file storage that could be useful for component R&D & project development, beyond the current instrument limitations.
The CRT's of these type of instruments are dying and are not easily replaceable.
Why not move forward with an inexpensive LCD module for these instruments ?
>>>? In any event, if anyone has direct technical experience with the type of XYZ CRT deflection signal pick-off and manipulation posed by this question, their experience or thoughts would be appreciated !
(i.e. , specifically for the Tek 576 CT,? would those signals have to be buffered or level shifted, etc. ?)
-- If anyone has come across a Website or a Blog conveying? *inexpensive*? vector XYZ CRT replacement ( or signal capture ) with an LCD,
I'd appreciate knowing about it !!
Not sure if there are other descriptions or jargon ( i.e.? " Scan Converter " etc. ) that might have been used to describe this sort of problem, perhaps published in "The Review of Scientific Instruments", or IEEE Transactions ?
There must have been sectors of the industry that encountered and solved this issue *inexpensively* ?
?
thank you,
rick?
Note:
-- A number of Web references for vector XYZ type concepts have been discussed, including a well explained reference to a Patent, in the Tek Groups .io discussion:?
/g/TekScopes/topic/86718765
-- Not worried about the Tek 576 switch settings / plastic fiber display issues for now;? - those are simply a decode issue which can be easily solved and added to the converted LCD display, later on !?
|
Re: Placing Shelf on Casters for HP Equipment
"Matt Huszagh via groups.io" <huszaghmatt@...> writes: Thanks Paul. So unfortunately, searching server rack rails on navepoint
didn't yield anything. I'm just seeing things like
that are mounted to the normal, front and back facing holes.
It looks like slotted angles might be a cheap way to get these. The one
trick is that these come in standard lengths, so 24" is common. But,
this is a bit too long for the 23.6" standard depth. And 12" is too
short. So, they'd need to be cut to length.
Also, on further thought these may not work because the supporting
portion of the angle will presumably need to sit exactly between each
1.75" unit. I'd also imagine they need to be 1/32" thick (since this is
how much shorter each module is than the number of rack units it takes
up). But, this seems to be a bit thin to be supportive. So, I'm confused
again.
Again, if anyone has a source for where to buy the appropriate side
supports that mount to these 90 degree holes I'd love to hear it. Ok, I think I finally found the key words. "19 inch rack support rails" seems to get me to the right items. For example, or Matt
|
Re: Placing Shelf on Casters for HP Equipment
Interesting idea - but if the rack is behind a bench, the drawers are a bit difficult to get to. Much depends on how yu position the equipment "racking" relative to the work space.
Cheers!
Bruce
Quoting "Michael A. Terrell" <terrell.michael.a@...>:
toggle quoted message
Show quoted text
I collected turntable drawers from old school intercom systems. With a
little work, I turned them into drawers to go in the lower part of racks to
store cables and small equipment.
On Mon, Nov 8, 2021 at 3:05 PM Bruce <bruce@...> wrote:
One disadvantage to racks is that it is difficult to utilize the space
below bench level. If you look at HP packaged configurations (HP
8510C for example) does not have front panel control or is controlled
ia GPIB.
True, things like power supplies can be used on the lower level, but
generally bench top access is required for test equipment - GPIB
control is an option but commercial software is expensive and
configuration management can be complicated.
Cheers
Bruce
Quoting Dave McGuire <mcguire@...>:
On 11/7/21 9:53 PM, Jim Ford wrote:
HP gear does have handles and rack ears that work together, at
least the 8566 spec an and 8530 sweep oscillator. Handy to keep
the handles on there, should rearrangement be necessary. The HP System I (example: 8640B) chassis system has handles built
into the side frame castings, and ears that work with them. The
System II (example: 8566, 8350) chassis systems have ears that work
standalone, and ears that work with handles.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: Placing Shelf on Casters for HP Equipment
"Paul Bicknell" <admin@...> writes: Thank you for the link to navepoint.com although they are more expensive but
a lot better
You ask
(Am I correct and thinking this satisfies method 3 you mentioned above?
I didn't actually see any navepoint side runners that mount to these
90degree holes though.
How do I search for these? Are they typically called "19 inch rack side
supports", or "19 inch rack runners", or something else? Or if you know of a
good source of these I'd be curious to hear it.)
Also called Rack Rails or 19 inch Side Rails
Look at the NavePoint site under SERVER RACK RAILS they also do shelves that
take up a 1 u depth but these are good to put equipment on that is not 19
inch wide
Personally I am not too keen on the counter poise shelves also thy might not
cope with long / deep test equipment
Configuring the rack I normally start with a 1 u blanking plate at the
bottom then a 2 u set of Power sockets in every other rack
Suggest you look out for horizontal power sockets on 19 in fixings also
vertical power sockets but this will depend on the rack configuration you
will require 10 + power sockets
You can also get 19 inch plates punched out for BNC bulk head sockets these
are useful for connections that are on the rear of the equipment that are
required at the front Thanks Paul. So unfortunately, searching server rack rails on navepoint didn't yield anything. I'm just seeing things like that are mounted to the normal, front and back facing holes. It looks like slotted angles might be a cheap way to get these. The one trick is that these come in standard lengths, so 24" is common. But, this is a bit too long for the 23.6" standard depth. And 12" is too short. So, they'd need to be cut to length. Also, on further thought these may not work because the supporting portion of the angle will presumably need to sit exactly between each 1.75" unit. I'd also imagine they need to be 1/32" thick (since this is how much shorter each module is than the number of rack units it takes up). But, this seems to be a bit thin to be supportive. So, I'm confused again. Again, if anyone has a source for where to buy the appropriate side supports that mount to these 90 degree holes I'd love to hear it. Matt
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Re: Placing Shelf on Casters for HP Equipment
I collected turntable drawers from old school intercom systems. With a little work, I turned them into drawers to go in the lower part of racks to store cables and small equipment.
On Mon, Nov 8, 2021 at 3:05 PM Bruce < bruce@...> wrote: One disadvantage to racks is that it is difficult to utilize the space?
below bench level.? If you look at HP packaged configurations (HP?
8510C for example) does not have front panel control or is controlled?
ia GPIB.
True, things like power supplies can be used on the lower level, but?
generally bench top access is required for test equipment - GPIB?
control is an option but commercial software is expensive and?
configuration management can be complicated.
Cheers
Bruce
Quoting Dave McGuire <mcguire@...>:
> On 11/7/21 9:53 PM, Jim Ford wrote:
>> HP gear does have handles and rack ears that work together, at?
>> least the 8566 spec an and 8530 sweep oscillator.? Handy to keep?
>> the handles on there, should rearrangement be necessary.
>
>? ?The HP System I (example: 8640B) chassis system has handles built?
> into the side frame castings, and ears that work with them.? The?
> System II (example: 8566, 8350) chassis systems have ears that work?
> standalone, and ears that work with handles.
>
>? ? ? ? ? ? ?-Dave
>
> --
> Dave McGuire, AK4HZ
> New Kensington, PA
>
>
>
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Re: Question: XY (XYZ or Vector) instrument CRT, replacement with an LCD ?
I like the AD623A differential amplifier?because it takes differential inputs and I can set the output to be 2.5v for 0v in.? Now?+5v out represents max positive input (say?+10V), 2.5v out represents 0v input, and 0v out represents max negative input (-100V). This scales the input to fit the 5 volt range of the ADC on a PIC. Adjust according to the ADC you are using. The schematic shows an application looking at a shunt in a 12v battery path and the output goes to a PIC ADC to read positive or negative current. R is the shunt. S2 is used to short the input to zero the amplifier with R7, it must be DPDT or you might be fighting the shunt for 10 amps. The 5v supply needs to be stable,?use?a precision?regulator with 5.000v out.. Peter??
Look at the schematics, the step amplifier for example. It shows 2v/div for the steps. Connect an instrument amplifier to the Steps Out and adjust the gain. The deflection amplifiers are trickier but can be done with an instrumentation amplifier with proper scaling and offsets. You will need to protect the circuit from the 100 volt signals. Good luck with the readout lamps for the ranges, but it is possible.? Peter
hi,
Just to pull the conversation back to the?? *electronics*? of the replacement of a XYZ CRT with an LCD ??
???? { rather than the programming or software, for now }.
Does anyone have any technical expertise with? "picking off" ? the vector type (non-raster) CRT XYZ signals? (presumably from the low voltage deflection amplifiers)? ?
Assuming that somewhere in the deflection amplifier signal chain, there might be some low voltage +/- 5V signals that could be used
? --- so that could then be fed into an LCD module ( such as the $55? STM32F746G-DISCO module ?).
For this project question, the CRT display is a simple XYZ vector display, not a raster CRT:
The NewScope modules are too expensive to consider,
and this CRT issue is not concerned with longevity nor with hypothetical future replacements of the LCD with another LCD, etc.
Nor with the use of yet another CRT.
The point being that the STM LCD module may represent the possibility of actually capturing the data from, say a Tek 576 Curve Tracer( as an example), that would allow such data to be imported into a laptop for data manipulation, comparison? and file storage that could be useful for component R&D & project development, beyond the current instrument limitations.
The CRT's of these type of instruments are dying and are not easily replaceable.
Why not move forward with an inexpensive LCD module for these instruments ?
>>>? In any event, if anyone has direct technical experience with the type of XYZ CRT deflection signal pick-off and manipulation posed by this question, their experience or thoughts would be appreciated !
(i.e. , specifically for the Tek 576 CT,? would those signals have to be buffered or level shifted, etc. ?)
-- If anyone has come across a Website or a Blog conveying? *inexpensive*? vector XYZ CRT replacement ( or signal capture ) with an LCD,
I'd appreciate knowing about it !!
Not sure if there are other descriptions or jargon ( i.e.? " Scan Converter " etc. ) that might have been used to describe this sort of problem, perhaps published in "The Review of Scientific Instruments", or IEEE Transactions ?
There must have been sectors of the industry that encountered and solved this issue *inexpensively* ?
?
thank you,
rick?
Note:
-- A number of Web references for vector XYZ type concepts have been discussed, including a well explained reference to a Patent, in the Tek Groups .io discussion:?
/g/TekScopes/topic/86718765
-- Not worried about the Tek 576 switch settings / plastic fiber display issues for now;? - those are simply a decode issue which can be easily solved and added to the converted LCD display, later on !?
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Paul Bicknell
Michael A. Terrell
Dave McGuire