Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1829247 times)

beanflying, BillB, SilverSolder, med6753 and 15 Guests are viewing this topic.

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4899
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25875 on: February 21, 2019, 05:40:22 am »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*
 

Offline 0culus

  • Super Contributor
  • ***
  • Posts: 1626
  • Country: us
  • Electronics, RF, and TEA Hobbyist
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25876 on: February 21, 2019, 05:48:33 am »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*

As long as they aren't flatheads, we're good.  :-DD
 

Online beanflying

  • Super Contributor
  • ***
  • Posts: 3717
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25877 on: February 21, 2019, 05:55:49 am »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*

As long as they aren't flatheads, we're good.  :-DD

No changing the original flat heads on those classic Cambridge decades lest you be struck down ;)
Coffee, Food, R/C and electronics nerd in no particular order :)
 

Offline 0culus

  • Super Contributor
  • ***
  • Posts: 1626
  • Country: us
  • Electronics, RF, and TEA Hobbyist
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25878 on: February 21, 2019, 06:22:49 am »
Nah I won't change screws that are already in there. But I won't use flatheads in any project I'm building.  :-+
 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4899
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25879 on: February 21, 2019, 06:29:16 am »
The ones in the body of these two are Fillister button heads; the one in the wooden box appears to have upholstery washers under those screws. The ones in the knobs are Fillister socket head screws.

I'd certainly NOT change either of them for flat head screws... any more than I'd "fix" them with a drywall screw.  :palm:

mnem
*Yawwwwnnnnn...  :=\*
 

Offline bitseeker

  • Super Contributor
  • ***
  • Posts: 7889
  • Country: us
  • Lots of engineer-tweakable parts inside!
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25880 on: February 21, 2019, 06:32:34 am »
Drywall screws...the duct tape of metal fasteners.
I TEA.
 

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 7429
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25881 on: February 21, 2019, 07:59:21 am »


Fuck me.

So... trial fitting the radiator to see which way the hoses will go best, and discover that the design of the case places the RAM on my MB too high. I can JUST get the radiator in on the outermost set of slots as I intended, but the frontmost fan occludes the top row of RAM lock-levers. I'll have to drop the RAD any time I need to reseat the RAM.  :palm: You can see how close the dimensions are in the pic I posted re: my thermal sensor.

A quick look on NewEgg shows that modern MBs, both AMD and Intel, have the RAM in the same location relative to the I/O header; so this is just plain poor layout in the case. The MB should have been located approx 20mm lower.  |O

The AIO does not want to play nicely in a front radiator install; the hoses are just a little too short. I specifically want top radiator anyways, so I get gravity-bleed and convection circulation if the pump dies.

I know I'm probably going to just suck it up and install with it blocking the RAM anyways... but right now I'm going to bed.

mnem
 :bullshit:
That's one reason why I have a full sized tower because the ram slots being so close to the top [emoji83]
Who let Murphy in?
 

Offline VK5RC

  • Supporter
  • ****
  • Posts: 2246
  • Country: au
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25882 on: February 21, 2019, 08:35:55 am »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*

As long as they aren't flatheads, we're good.  :-DD



No changing the original flat heads on those classic Cambridge decades lest you be struck down ;)

Isn't the "Proper" screw a slotted cheese head for that equipment. I haven't seen a new one in decades - bloody torx, Phillips and posidrive rubbish - harrumph!
Whoah! Watch where that landed we might need it later.
 

Online beanflying

  • Super Contributor
  • ***
  • Posts: 3717
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25883 on: February 21, 2019, 08:45:01 am »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*

As long as they aren't flatheads, we're good.  :-DD



No changing the original flat heads on those classic Cambridge decades lest you be struck down ;)

Isn't the "Proper" screw a slotted cheese head for that equipment. I haven't seen a new one in decades - bloody torx, Phillips and posidrive rubbish - harrumph!

Yes! Yes they are - Documentary evidence in case of secret exchanges to inferior fasteners :-DD

'Proper' screws prior to export ;)


Coffee, Food, R/C and electronics nerd in no particular order :)
 
The following users thanked this post: VK5RC, mnementh

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11606
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25884 on: February 21, 2019, 10:07:16 am »
Ok so this weekend's project is the Tek 475A. I need to fix the timebase problem which is no sweep on two timebase settings and fix all the knackered bulbs. I know what the first issue is (damn leaf switches again) but the bulbs I'm trying to make a decision over.

I have got a whole bag of bulbs to go in it but I really don't want to take this to bits again one day so I'm thinking of retro-fitting cheap chinese warm white 3mm LEDs instead. I have a billion of these. They have a forward current of 20mA approx to get the same brightness as the bulbs and in most circumstances, at least in the timebase, these will be fine as they are just switched. Probe indicators might require some further thought. Should look original-ish with those in rather than some lurid red/green LED colour.
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 4049
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25885 on: February 21, 2019, 11:48:44 am »
Ok so this weekend's project is the Tek 475A. I need to fix the timebase problem which is no sweep on two timebase settings and fix all the knackered bulbs. I know what the first issue is (damn leaf switches again) but the bulbs I'm trying to make a decision over.

I have got a whole bag of bulbs to go in it but I really don't want to take this to bits again one day so I'm thinking of retro-fitting cheap chinese warm white 3mm LEDs instead. I have a billion of these. They have a forward current of 20mA approx to get the same brightness as the bulbs and in most circumstances, at least in the timebase, these will be fine as they are just switched. Probe indicators might require some further thought. Should look original-ish with those in rather than some lurid red/green LED colour.

The 465B is a combo of LED/incandescent already. Incandescent for both volts/div switches and then LED's for everything else. As I recall the 465 junker was incandescent/NE-2 neon driven from the 110VDC supply. Isn't the 475A more like the 465 with that same combo or is it all incandescent? It's been at least 35 years since I last played with a 475A so I don't recall. 
An old gray beard with an attitude.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11606
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25886 on: February 21, 2019, 12:32:23 pm »
This 475A is entirely incandescent. Fortunately all low voltage. No neons. that would require some rework to get LEDs in there. Due to the design of the 475A I can slide these in with a resistor change and dropping an LED in the old bulb holes.
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 4049
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25887 on: February 21, 2019, 01:19:08 pm »
Even if they were neon you could still sub in an LED. It would just have to require a HUGE dropping resistor. But.....subbing in LED's might put a drag on the 110VDC supply because LED's consume 20ma and neon bulbs almost nothing. Luckily you don't have to worry about that.

If I had the white LED's already on hand I would replace the incandescent.
An old gray beard with an attitude.
 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4899
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25888 on: February 21, 2019, 01:19:45 pm »
Heh... y'all will hate me for suggesting it, but the first thing I thought when I saw it was "I wanna replace all the fasteners with stainless button head allen screws."  :-DD

mnem
*HotWod Dwagon, thwough & thwough*

As long as they aren't flatheads, we're good.  :-DD



No changing the original flat heads on those classic Cambridge decades lest you be struck down ;)

Isn't the "Proper" screw a slotted cheese head for that equipment. I haven't seen a new one in decades - bloody torx, Phillips and posidrive rubbish - harrumph!

Yes! Yes they are - Documentary evidence in case of secret exchanges to inferior fasteners :-DD

'Proper' screws prior to export ;)

Cheese head screws are have a thicker root (The area of solid metal under the slot). Those are pan head screws. However, the ones IN the knobs may be cheesehead. Buttonhead screws are domed; proper ones are like the screws in the body of jwc's decade box. The ones that are popular today are kindof halfway between, because they are easier to forge as Philips and the reduced pressure required makes dies last longer. They are still usually called buttonhead.

mnem
 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4899
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25889 on: February 21, 2019, 01:39:33 pm »
   ...I know I'm probably going to just suck it up and install with it blocking the RAM anyways... but right now I'm going to bed.

mnem
 :bullshit:
That's one reason why I have a full sized tower because the ram slots being so close to the top [emoji83]



Yeah, yeah... this is a mid-tower with what looks like oodles of room; it's just poorly thought out. Or rather, appearance was weighted over function in the engineering scope. Another product designed by committee.  :palm:

I used to be the same way about huge tower cases... but really, I have to live with this thing. I don't need another man-eating big black box in the living room. The subwoofer already has cable envy; I don't want to give it an inferiority complex on top of that. :-DD

mnem
No, thanks. I'm trying to cut back.  ;)
 

Offline neo

  • Super Contributor
  • ***
  • Posts: 1696
  • Country: us
  • The specialist.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25890 on: February 21, 2019, 01:44:42 pm »
HP 141T teardown, they make those caps impossible to read and seemingly impossible to remove.








Anyone enjoying these?
« Last Edit: February 21, 2019, 01:48:33 pm by neo »
A hopeless addict (and slave) to TEA and a firm believer that high frequency is little more than modern hoodoo.
 
The following users thanked this post: mnementh

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11606
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25891 on: February 21, 2019, 02:05:07 pm »
Thanks for the 141T teardown.

I have nearly bought a couple of them recently but was scared off by the mechanical problems with the plugins and the lack of any decent pictures.

I am now thoroughly put off with the idea  :-DD
 

Offline nixiefreqq

  • Frequent Contributor
  • **
  • Posts: 386
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25892 on: February 21, 2019, 02:39:39 pm »
HP 141T teardown, they make those caps impossible to read and seemingly impossible to remove.


Anyone enjoying these?


enjoying?   well those pics sure are bringing back lots of memories (and may lead to nightmares).  spent waaaaaaay too much time inside those things.

but when you get it working you will appreciate why 40 years ago we all drooled over them.  so many knobs to fiddle with! 

takes a while to get used to the implications of harmonic mixing, but after you get used to flicking the "signal identifier" switch to prove you are looking at the correct peak it stops bothering you that some signals you can see do not match the band switch setting.

playing with the storage settings is almost more fun than a video game. 

AND if you really like fixing things they are a gift that keeps on giving.   (zoooooorrrrrrch!)



edit--  but they were and still are good instruments, and very very useful tools.


« Last Edit: February 21, 2019, 02:52:33 pm by nixiefreqq »
"free range primate"
 

Offline Brumby

  • Supporter
  • ****
  • Posts: 9239
  • Country: au
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25893 on: February 21, 2019, 02:50:23 pm »
When I saw the video Bean put up about the 8656B attenuator, my interest was piqued.


The mechanical aspect of the repair was not particularly intimidating
- but my unit did things differently...


Not to worry, I located the low band input to the attenuator (up to 123.5MHz), unscrewed the SMA connector and hooked it up to a scope.  Played around with all the controls and the signal did what I expected - so the attenuator does, indeed, appear to be the problem.  Need to check out the junker.


And here's another gratuitous shot of a little flash of gold...
« Last Edit: February 21, 2019, 02:52:12 pm by Brumby »
 
The following users thanked this post: beanflying

Online med6753

  • Super Contributor
  • ***
  • Posts: 4049
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25894 on: February 21, 2019, 03:29:26 pm »
HP 141T teardown, they make those caps impossible to read and seemingly impossible to remove.

Anyone enjoying these?

Pray tell, what caps are you referring to? I see a CRT, a relay, couple of TO-3's, and a few circuit boards. What caps? They must be hidden real good.  :-DD
An old gray beard with an attitude.
 

Offline neo

  • Super Contributor
  • ***
  • Posts: 1696
  • Country: us
  • The specialist.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25895 on: February 21, 2019, 03:34:16 pm »
HP 141T teardown, they make those caps impossible to read and seemingly impossible to remove.


Anyone enjoying these?


enjoying?   well those pics sure are bringing back lots of memories (and may lead to nightmares).  spent waaaaaaay too much time inside those things.

but when you get it working you will appreciate why 40 years ago we all drooled over them.  so many knobs to fiddle with! 

takes a while to get used to the implications of harmonic mixing, but after you get used to flicking the "signal identifier" switch to prove you are looking at the correct peak it stops bothering you that some signals you can see do not match the band switch setting.

playing with the storage settings is almost more fun than a video game. 

AND if you really like fixing things they are a gift that keeps on giving.   (zoooooorrrrrrch!)



edit--  but they were and still are good instruments, and very very useful tools.

Oh i'm more than aware WHY people drool over them. Hell, i've yet to have it working and i'm drooling over it. I meant a more in general question, 'why am i doing this?' type question. Little discouraged is all because of my current (seeming) inability to do much except for taking it apart and scratching my head.

HP 141T teardown, they make those caps impossible to read and seemingly impossible to remove.

Anyone enjoying these?

Pray tell, what caps are you referring to? I see a CRT, a relay, couple of TO-3's, and a few circuit boards. What caps? They must be hidden real good.  :-DD
@Med These caps and one under the relay.  |O

A hopeless addict (and slave) to TEA and a firm believer that high frequency is little more than modern hoodoo.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11606
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25896 on: February 21, 2019, 03:49:46 pm »
Bloody hell. That's a capacitor nightmare that.
 

Offline neo

  • Super Contributor
  • ***
  • Posts: 1696
  • Country: us
  • The specialist.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25897 on: February 21, 2019, 04:11:45 pm »
Bloody hell. That's a capacitor nightmare that.
The whole things a bloody nightmare. Especially the lack of any kind of test point so i have no idea what to ground to or where to probe. |O
A hopeless addict (and slave) to TEA and a firm believer that high frequency is little more than modern hoodoo.
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 4049
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25898 on: February 21, 2019, 04:13:24 pm »
Bloody hell. That's a capacitor nightmare that.
The whole things a bloody nightmare. Especially the lack of any kind of test point so i have no idea what to ground to or where to probe. |O

Ah ha! There they is.  ;D Good luck!  :o :-DD
An old gray beard with an attitude.
 

Online med6753

  • Super Contributor
  • ***
  • Posts: 4049
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #25899 on: February 21, 2019, 04:22:22 pm »
Question for tautech. Hopefully he'll see this later when he wakes up.

Siglent SD1052DL. If both channels are connected and I hit "Auto" to trigger it always defaults to channel 2. How can I change the default to channel 1?

An old gray beard with an attitude.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf