Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 20877097 times)

nikodem, duckduck, theHWcave and 52 Guests are viewing this topic.

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133125 on: February 26, 2023, 09:26:56 pm »


TEK 7603 scope restoration

Just realized there is one thing I forgot to mention strangely, because it's a show stopper for using this scope in practice : the cooling fan is freaking loud, unbearable.
Even when you turn the scope off, the fan still makes a horrible noise until it's 100% stopped.

I guess the bearing in it must be badly shot... too much for a lubrication service to bring it back to like, though I can try anyway I guess.

So I would be looking at a replacement fan. Looking at the parts list, it's made by " IMC Magnetics ", model MBS-2107F-0-1

115Vac , 46 CFM, 19 Watts, 200mA.

It does not state dimensions and bolt pattern though, so I would have to excavate it from the scope, more work.
It's a thick model.
Found one on Ebay :

https://www.ebay.com/itm/266068416615

Pictures there show the fan next to a measuring tape, though the latter is positioned in a strange way, not sure what the seller was trying to measure here.
Bad news is, it looks to be more than 10cm, but a bit less than 12cm. Which means it's not a standard size so I am screwed, great....  :palm:


Popped the PSU cover at the back of the scope   Measured the thing up.

Overall / Max dimensions =  90x90mm
Pitch for the mounting screws : 82x82mm
Thickness : 38mm

So it's 90mm... let's see if that's a standard size... not too hopeful, never heard of a 90mm fan before... thought it was either 80 or 120mm...


EDIT : a quick Google suggests that 90mm fans do exist after all, lucky me... I will do some research and see if I can find something with the correct thickness and electrical specs and CFM...

« Last Edit: February 26, 2023, 09:35:17 pm by Vince »
 
The following users thanked this post: Neomys Sapiens

Offline Neomys Sapiens

  • Super Contributor
  • ***
  • Posts: 3268
  • Country: de
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133126 on: February 27, 2023, 12:08:56 am »

TEK 7603 scope restoration

So it's 90mm... let's see if that's a standard size... not too hopeful, never heard of a 90mm fan before... thought it was either 80 or 120mm...

As much as I love their 'scopes, Tektronix seems to have staffed their component engineering department with some malicious entities. I bet it reeked of sulfur in there.

But I like what you are doing. This is going to end well, I think.
 
The following users thanked this post: Vince, ch_scr

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133127 on: February 27, 2023, 06:44:29 pm »
OK gave it a go : I tried oiling the fan to see it made any difference :

Removed the sticker, which  then showed me circlip, removed that with my tweezers (don't have the special pliers for these things).
This allowed me to remove a dust cap, destroying it in the process, no choice.

That gave access to another dust cap, had to destroy / mangle that one too when prying it out.
Under that cap was a rubber seal laying on the ball bearing, removed that.

Then another circlip, tiny one, grabbing the shaft. Difficult to remove it was.
Then I could at last removed the fan itself/rotor assembly, and make nice pics for you.

I knew you would like it, no need to thank me.

So we have two small ball bearings in there.

Removed the old sticky grease, put some machine oil in there. Yes I am sure grease is better in the long run, but the old one was too sticky. Sue me.

Reassembled, fired up the scope : as I thought... no improvement, those bearings are well shot.

You know what ? I am feeling motivated... I am wondering if I could maybe manage to replace those bearings ?
I will measure them up and see if it's a standard size I could get somewhere for cheap.
If it is, might give it a go. I have no idea I would proceed to remove the old bearings just yet, but I have nothing to lose.

Point is, this fan is no cheaper crappy plastic modern unit. No, it's a heavy beefy alloy die cast monster, it's very sexy in person.
Would be a shame to throw it in the trash. Would be much more cool and satisfying if I could revive it.

As for getting a new/replacement fan, I am thinking it's not a good idea to search for 115Vac ones....  we are in Europe here.
I would no doubt have a lot more choice if I searched for 230Vac fans. It should not be terribly difficult to alter the wiring of the fan in the scope to tap mains voltage rather than 115V...

That's all for today, you can now resume your normal activities.

« Last Edit: February 27, 2023, 07:40:46 pm by Vince »
 
The following users thanked this post: ch_scr, factory, duckduck, extremgear

Offline extremgear

  • Contributor
  • Posts: 22
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133128 on: February 27, 2023, 07:01:16 pm »
OK gave it a go : I tried oiling the fan to see it made any difference :

Removed the sticker, which  then showed me circlip, removed that with my tweezers (don't have the special pliers for these things).
This allowed me to remove a dust cap, destroying it in the process, no choice.

That gave access to another dust cap, had to destroy / mangle that one too when prying it out.
Under that cap was a rubber seal laying on the ball bearing, removed that.

Then another circlip, tiny one, grabbing the shaft. Difficult to remove it was.
Then I could at last removed the fan itself/rotor assembly, and make nice pics for you.

I knew you would like it, no need to thank me.

So we have two small ball bearings in there.

Removed the old sticky grease, put some machine oil in there. Yes I am sure grease is better in the long run, but the old one was too sticky. Sue me.

Reassembled, fired up the scope : as I thought... no improvement, that bearing are well shot.

You know what ? I am feeling motivated... I am wondering if I could maybe manage to replace those bearings ?
I will measure them up and see if it's a standard size I could get somewhere for cheap.
If it is, might give it a go. I have no idea I would proceed to remove the old bearings just yet, but I have nothing to lose.

Point is, this fan is no cheaper crappy plastic modern unit. No, it's a heavy beefy alloy die cast monster, it's very sexy in person.
Would be a shame to throw it in the trash. Would be much more cool and satisfying if I could revive it.

As for getting a new/replacement fan, I am thinking it's not a good idea to search for 115Vac ones....  we are in Europe here.
I would no doubt have a lot more choice if I searched for 230Vac fans. It should not be terribly difficult to alter the wiring of the fan in the scope to tap mains voltage rather than 115V...

That's all for today, you can now resume your normal activities.
bearings are very cheap these days, to me replacing the bearings rather than the complete fan is the way to go, you could buy them online,  you can try 123roulements.
Also your fan doesn't have other worn parts like brushes or collector, after replacing the bearings you will end up with a completely new fan !
 

Offline Robert763

  • Super Contributor
  • ***
  • Posts: 2891
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133129 on: February 27, 2023, 09:12:50 pm »
@Vince
Measure the bearings (outer diameter, inner diameter and thickness) besy you can. I might have some. I have a lot of new old stock sealed in the packet instrument and gyro bearings. You could get lucky...

Robert.

 
The following users thanked this post: Vince

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133130 on: February 27, 2023, 09:18:02 pm »
Wow I am reallym otiated it seems.... I removed the scope from the scope to look at the bearings... if there was any chance I could remove them despite having only standard / basic tools.

I got lucky.

1) the one at the bottoom of the stator, buried deep inaccessible to tools..... actually came right off as I pulled the fan / rotor ! I pulled the rotor and the bearing had lifted from teh bottom of the stator, almost all the way up the shaft ! I noly had to pick it with my fingers and slide the remaining 5mm to free it from the shaft... it was a transient fit, lucky me. I guess putting mahcine oil in the thing last night must have helped...

2) Now the other bearing, inside the rotor. First I tried to push on it from the ouside. No luck. It did move but would come back immediately, as if it were sitting on a spring ! Well why not.
So instead I tried sticking a small screwdriver inside teh rotor to push on the bearing from the back, outwards. That did it, the bearing and its spring came right out, yeah !  :-+

The spring is a mess though... it's not a single piece coil spring, but rather a stack of 6 or 8 washers. Half of them are flat, interleaved with the other halff which have a "wavy" shape, that give this springy action I guess.

I think there were a washer or two somewhere else but I forgot where. Toob ad.. I hope the fan will still work, we shall see.

So I have the two bearings freeed now, cool. They are identical.

I measured them up, and that's where the bad news start...

Outside diameter = 9.5mm
Inner diameter = 4.62mm
Thickness = 3.15mm

So... what the heck are those weird ass dimensions... good luck finding that off the shelves... will try anyway but not holding my breath.

It needs to be the exact same dimensions or it won't work... a hair too big and I won't be able to fit them, too much interference.
A hair smaller and they will be loose.

 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133131 on: February 27, 2023, 09:18:57 pm »
@Vince
Measure the bearings (outer diameter, inner diameter and thickness) besy you can. I might have some. I have a lot of new old stock sealed in the packet instrument and gyro bearings. You could get lucky...

Robert.

Oh, our posts collided.... I just posted the dimensions, have a look ! Thanks for the offer !  :)
 

Offline factory

  • Super Contributor
  • ***
  • Posts: 3243
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133132 on: February 27, 2023, 09:34:19 pm »
As the fan is probably made in the US, all the sizes will be imperial, not metric.

Outside diameter = 9.5mm, converts to approx 0.374", check again as it might be 0.375" aka 3/8"
Inner diameter = 4.62mm, converts to approx 0.1819" did you measure the motor shaft, or the bearing hole?
Thickness = 3.15mm, converts to approx 0.124", check as it might be 0.125" aka 1/8"

And my Mouser order arrived today, only 9 out to 10 items were correct, got sent a bag labelled connectors, filled with some unidentified surface mount part. Also got a bonus letter from someone else's order.  :palm:


Thankfully the returns process was painless, but it leaves me having to reorder the connectors they should have sent.  |O

David
« Last Edit: February 27, 2023, 09:47:36 pm by factory »
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133133 on: February 27, 2023, 09:36:23 pm »
OK I gave the French website a try, 123roulement.fr ... to my surprise it seems that my dimensions are actually standard ?!  :-DMM

I measured 9.5mm and they have values around that :

- 9.5mm
- 9.52
- 9.525
- 9.53

Any of these would do I think.

Then for the thickness, I measured 3.15mm and they don't have that but they have tons of products with a thickness of 3.17mm ... good enough.

Last, the inner diameter. I measured 4.62mm and they don't have that. The standard size seems to be a tad larger, 4.7+.

As for the exact dimensions not all combinations are available, and many are not in stock... but I found this one that looks close enough, in stock, quick delivery.

https://www.123roulement.com/roulements-R166-2RS

9.52 x 4.76 x 3.17.

They have 15 in stock, 4.30 Euros a pop tax included. Need two of them, 8.60 + shipping is reasonable at under 4.31 Euros. All in, it's 12 Euros. Tempting...

« Last Edit: February 27, 2023, 09:51:34 pm by Vince »
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133134 on: February 27, 2023, 09:39:18 pm »
As the fan is probably made in the US, all the sizes will be imperial, not metric.

Outside diameter = 9.5mm, converts to approx 0.374", check again as it might be 0.375" aka 3/8"
Inner diameter = 4.62mm, converts to approx 0.1819" did you measure the motor shaft, or the bearing hole?
Thickness = 3.15mm, converts to approx 0.124", check as it might be 0.125" aka 1/8"

David

Yes I think you must be right. The sizes on the French website are all nonsensical in the metric world, so must be rounded imperial units.

Inner diameter I measured the inside of the bearing, so not so accurate / reliable compared to an outer measurement... I must have underestimated it a bit or plain read the scale wrong maybe... will try again.

 

Offline factory

  • Super Contributor
  • ***
  • Posts: 3243
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133135 on: February 27, 2023, 09:43:03 pm »
Measure the motor shaft instead, trying to measure tiny inside diameters isn't easy without more specialist tooling.

David
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133136 on: February 27, 2023, 09:56:31 pm »
The shaft just measured at 4.70mm great.. so that new bearing with a diameter of 4.76 should be perfect, a nice transition fit...

 

Offline dzseki

  • Frequent Contributor
  • **
  • Posts: 524
  • Country: hu
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133137 on: February 27, 2023, 09:57:11 pm »
A colleague of mine have offered his old spectrum analyzer for sale. Nothing fancy, it is a Promax (Spanish TE manufacturer) AE476 model. It was made in the late 80's or early 90's, full discrete build up (but there is no ducumentation for it), It is fairly straightforward to use, not too many parameters to set. It is definitely a budget model with not so great specs, but looks usable for general use...
The price is about 170€.
I don't have a SA at home, and so far I could get away without it, but hey, this is the TEA thread right? One can always find an expensive SA on the market, but cheap SAs are scarce.

Would you buy it?
HP 1720A scope with HP 1120A probe, EMG 12563 pulse generator, EMG 1257 function generator, EMG 1172B signal generator, MEV TR-1660C bench multimeter
 
The following users thanked this post: Vince, duckduck

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133138 on: February 27, 2023, 10:15:12 pm »
Well if it fits your needs go for it.... for that price, hard to beat.

It's in good nick cosmetically, it appears to be working, it's got a 50ohm input (the cheap SA usually are cheap because they are 75R not 50), and... and... it's got a tracking generator output !!!  :-DMM

For hobby use, that feature is worth more than all the bells and whistles of the XX times more expensive SA's, I say.

You can always buy a fancier SA later if you wish... I say for 170 Euros, it's good value to me... you can always sell it later anyway.

 
The following users thanked this post: dzseki

Offline dzseki

  • Frequent Contributor
  • **
  • Posts: 524
  • Country: hu
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133139 on: February 27, 2023, 10:22:55 pm »
Well if it fits your needs go for it.... for that price, hard to beat.

It's in good nick cosmetically, it appears to be working, it's got a 50ohm input (the cheap SA usually are cheap because they are 75R not 50), and... and... it's got a tracking generator output !!!  :-DMM

For hobby use, that feature is worth more than all the bells and whistles of the XX times more expensive SA's, I say.

You can always buy a fancier SA later if you wish... I say for 170 Euros, it's good value to me... you can always sell it later anyway.

Actually, the tracking generator is not the original one. This SA apparently missed this option originally, and it was retrofitted by my colleague (a modified SAT LNB, he said), it kinda works but  not a super flat response with a single cable, say +/-5dB.
I saw the company is still around selling rebadged far-east instruments (as I see), I think I drop them an e-mail if they have the SM available...
HP 1720A scope with HP 1120A probe, EMG 12563 pulse generator, EMG 1257 function generator, EMG 1172B signal generator, MEV TR-1660C bench multimeter
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 29894
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133140 on: February 27, 2023, 10:27:26 pm »
Vince, imperial
OD =3/8" = 0.375"
L = 1/8" = 0.125"
ID = 3/16" = 0.1875"
Sorry, had L and ID mixed up, now corrected.

All small but standard size.....where did you say that fan was made ?

https://www.jgmes.com/webstart/library/table_frac.htm
« Last Edit: February 27, 2023, 11:13:04 pm by tautech »
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 

Offline timeandfrequency

  • Frequent Contributor
  • **
  • Posts: 286
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133141 on: February 27, 2023, 10:28:02 pm »
Measure the motor shaft instead, trying to measure tiny inside diameters isn't easy without more specialist tooling.
Hi David,

Sometimes you can use your twist drill bit set to approximate.
You may also add one layer of rolling paper on the drill bit shaft to get closer to the actual bore diameter.
Measure your 'tool' with a caliper to obtain a precise value.

For bore sizes 3-13mm (about 1/8" to 1/2"), these tools are cost effective and can provide accurate inside diameter values ​​better than 10µm when used with a good quality outside micrometer. With a standard vernier caliper, 100µm is still achievable.
« Last Edit: February 27, 2023, 10:38:13 pm by timeandfrequency »
 
The following users thanked this post: duckduck

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133142 on: February 27, 2023, 10:47:31 pm »
Vince, imperial
OD =3/8" = 0.375"
ID = 1/8" = 0.125"
L = 3/16" = 0.1875"

All small but standard size.....where did you say that fan was made ?

https://www.jgmes.com/webstart/library/table_frac.htm

It's made in the USA / funny units land, by "IMC Magnetics", in Rochester, New Hampshire.
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 29894
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133143 on: February 27, 2023, 10:57:38 pm »
Vince, imperial
OD =3/8" = 0.375"
L = 1/8" = 0.125"
ID = 3/16" = 0.1875"
Sorry, had L and ID mixed up, now corrected.

All small but standard size.....where did you say that fan was made ?

https://www.jgmes.com/webstart/library/table_frac.htm

It's made in the USA / funny units land, by "IMC Magnetics", in Rochester, New Hampshire.
:-+
Use imperial those measurements to find replacements and just double check the 3/16" one.
Do you have imperial calipers ?
« Last Edit: February 27, 2023, 11:14:34 pm by tautech »
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133144 on: February 27, 2023, 11:07:16 pm »
No, no imperial calipers, but I have a calculator....

It's clear now my bearings are imperial and it's clear that French website sells imperial converted/rounded to metric.  Here in Metric land we have no particular interest in making a bearing that's 3.17mm thick... so it means it's 1/8" and that's it.... inner diameter is close to 4.8mm so must be 3/16".

I am about to pull the trigger... and the website accepts Paypal as well, 3.....2.....1.......No, waiting for Robert's reply, maybe he has some.... in box #435,  3rd garage, 5th alley, 17th pile, 9th box counting from the floor. In the box, sub-box 12, in a little zip bag marked #32.   Or is it #31....

 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133145 on: February 27, 2023, 11:15:12 pm »



For those who know the difference and appreciate these things.... there is a Metrix MX53C that just popped up here, in good nick and complete, for 60 Euros (50/55 Quid or something ?),  That's good value. Even has the rubber bumper says the seller, but it's not shown on the pictures so that would need clarifying.

https://www.leboncoin.fr/outillage_materiaux_2nd_oeuvre/2307730512.htm


I am tempted but have many of them already so I am trying not to be too selfish, and let others have one as well. How nice I am .
« Last Edit: February 27, 2023, 11:23:11 pm by Vince »
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 29894
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133146 on: February 27, 2023, 11:16:38 pm »
No, no imperial calipers, but I have a calculator....
Not even a 3/16" drill bit ?

Edits made to ID and L measurements previously mixed up.  |O
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133147 on: February 27, 2023, 11:19:30 pm »
No, I am France, there is no reason I would have imperial drill bits. Hell I would kill to know where to buy good quality METRIC ones... the ones I got at H/W store are trash... supposedly a good French Brand, Tivoly... my ass. All they can drill into is butter, barely.
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 29894
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133148 on: February 27, 2023, 11:37:06 pm »
No, I am France, there is no reason I would have imperial drill bits. Hell I would kill to know where to buy good quality METRIC ones... the ones I got at H/W store are trash... supposedly a good French Brand, Tivoly... my ass. All they can drill into is butter, barely.
:-//
Had metric, imperial and # drills for decades.
Metric and imperial are everyday hobby sizes while # drills are somewhat more specialised.
Taps and dies carried are BSPT, BSW, UNC, UNF and ISO Metric mainlining on coarse/medium pitch depending on the thread charts you read.
Takes a good few years to become comfortable with both.
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 

Offline Vince

  • Super Contributor
  • ***
  • Posts: 4372
  • Country: fr
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #133149 on: February 27, 2023, 11:46:09 pm »
That's because you are an old nerd, you have everything, collecting for decades  ;)

Ask how many american TEA member have as many metric this or that, as they have imperial ?.....

I live in a metric continent so of course that's what I buy / need...

Working on restoring old Tek and HP gear of course has me buy the odd imperial this or that to get things done, but only the very tools I need.

I am not going to buy imperial stuff unless I have an actual and immediate need for it.

So I bought a 1/16" Allen screw driver because Tek use that for all the set screws for their knobs and shaft couplers... so I found it a good investment. But I am not gonna wste tons of money to buy a comprehensive set of every size that I have no use right now...same for drill bits.

At work we have digital calipers that can convert the display to inches, but it's not magical, it will use the decimal notation not fractions of inches... so not much help for an american who needs to know the fractions notation.

It's 00H45, time to go to bed...  :=\

 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf