Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1831555 times)

beanflying, Jambalaya, scl and 8 Guests are viewing this topic.

Online tautech

  • Super Contributor
  • ***
  • Posts: 16024
  • Country: nz
  • Taupaki Technologies Ltd. NZ Siglent Distributor
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37000 on: August 16, 2019, 08:54:20 pm »
Yea, I guess I'm an old junk junkie.  :-DD
Tek junkie is missing ^^  :-//

5 scopes here need fixing and one is a Tek DSO.
HP, Philips x2, an Aaron plus the Tek that was my first compact DSO.
Avid Rabid Hobbyist
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37001 on: August 16, 2019, 08:56:36 pm »
OK, more specific Old Tek Junk Junkie.  :-+ :-DD
An old gray beard with an attitude.
 
The following users thanked this post: tautech, mnementh

Online tautech

  • Super Contributor
  • ***
  • Posts: 16024
  • Country: nz
  • Taupaki Technologies Ltd. NZ Siglent Distributor
    • Taupaki Technologies Ltd.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37002 on: August 16, 2019, 09:01:44 pm »
OK, more specific Old Tek Junk Junkie.  :-+ :-DD
You do good work Med and I enjoy reading your battles and fixes.  :)
Avid Rabid Hobbyist
 
The following users thanked this post: med6753

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 7431
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37003 on: August 16, 2019, 09:11:37 pm »
OK, more specific Old Tek Junk Junkie.  :-+ :-DD
You do good work Med and I enjoy reading your battles and fixes.  :)
I think you speak for us all on that topic. I enjoy the repairs, always something to be learnt but personally I'd rather be repairing something new to me, or something that will earn a buck or two help fund my TEA, than keep repairing the test gear that I should be using [emoji4]

Perhaps one day I too might be able to get all new kit but for now I'm happy with kit that is 30 years or less old with low hours of use on them. My oldest bits of kit are older but seldom used, their RF signal generators but judging by their condition have had very low usage in their life, [emoji106]

Sent from my POT-LX1 using Tapatalk
« Last Edit: August 16, 2019, 09:17:41 pm by Specmaster »
Who let Murphy in?
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37004 on: August 16, 2019, 09:20:11 pm »
OK, more specific Old Tek Junk Junkie.  :-+ :-DD
You do good work Med and I enjoy reading your battles and fixes.  :)
I think you speak for us all on that topic. I enjoy the repairs, always something to be learnt but personally I'd rather be repairing something new to me, or something that will earn a buck or two help fund my TEA, than keep repairing the test gear that I should be using [emoji4]

Perhaps one day I too might be able to get all new kit but for now I'm happy with kit that is 30 years or less old with low hours of use on them. My oldest bits of kit are older but seldom used, their RF signal generators but judging by their condition have had very low usage in their life, [emoji106]

Sent from my POT-LX1 using Tapatalk

If your intention is to turn an item around and sell it to fund other purchases then that makes total sense. But I purchase and keep because that's what I want in my collection. So I don't mind if I gotta fix it. And if something does break while I'm troubleshooting other equipment I have backups.

Edit....the 475A is back in the case and it's been running for hours and channel 1 is working fine.  :-+
« Last Edit: August 16, 2019, 09:22:58 pm by med6753 »
An old gray beard with an attitude.
 
The following users thanked this post: Cubdriver

Offline GregDunn

  • Frequent Contributor
  • **
  • Posts: 723
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37005 on: August 16, 2019, 09:35:48 pm »
UFO wasn't too bad. There was an internal logic, and that and physics weren't ignored form the sake of the current episode's plot. In that sense it was a live action follow on to Thunderbirds.

Basically I found UFO to be entertaining for one or two episodes. But Space 1999 made me want the throw something at the TV after 15 minutes.

Same here - 1999 reached its nadir with the "green tongue monster" episode.  I only ran across it by accident, because there's no way I'd intentionally tune in to that piece of poop.

UFO actually had some very good moments - when people have todo their job, make hard choices and it destroys a family or a relationship, that's not formulaic TV.  It also eschewed the "monster of the week" or "melodrama of the week" plots, which kept even the lesser episodes from being disasters.
 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 4902
  • Country: us
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37006 on: August 16, 2019, 11:38:18 pm »
   You mean this guy? Yeah... some truly LAZY setbuilding coupled with with "spew & a half" acting... and this from a guy with fond memories of the "K-9 years" on Doctor Who...  :o

mnem
*currently just starting on the David Tennant years with my kids*
« Last Edit: August 16, 2019, 11:40:09 pm by mnementh »
 

Online 0culus

  • Super Contributor
  • ***
  • Posts: 1626
  • Country: us
  • Electronics, RF, and TEA Hobbyist
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37007 on: August 17, 2019, 02:28:43 am »
Received a goodie box of 7k series plugins. Pair of 7A26 amplifiers, a 7A13 differential comparator, and a 7A22 differential amplifier. Also a P6046 differential probe. Pics to come this weekend.

...now I need P6055 probes for the differential plugins.  :-DD
 
The following users thanked this post: bd139

Offline bsfeechannel

  • Frequent Contributor
  • **
  • Posts: 834
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37008 on: August 17, 2019, 06:29:21 am »
We call vacuum tubes valves because they control the flow of electrons I guess [emoji16]

You call them valves because Fleming called them valves.
« Last Edit: August 17, 2019, 07:02:32 am by bsfeechannel »
 

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 7431
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37009 on: August 17, 2019, 07:02:55 am »
We call vacuum tubes valves because they control the flow of electrons I guess [emoji16]

You call them valves because Flemming called them valves.
That maybe, but why did Flemming call them valves is the question then and being purely logical, might it be that he called them valves because of their ability to control the flow of electrons in a similar fashion to valves controlling the flow of a liquid or gas?
Who let Murphy in?
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11610
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37010 on: August 17, 2019, 07:32:09 am »
We call vacuum tubes valves because they control the flow of electrons I guess [emoji16]

You call them valves because Flemming called them valves.
That maybe, but why did Flemming call them valves is the question then and being purely logical, might it be that he called them valves because of their ability to control the flow of electrons in a similar fashion to valves controlling the flow of a liquid or gas?

Well the first flemming valve was only a rectifier so I suppose that makes sense. I’m not sure it does for a triode etc. That’s a little more complicated due to the characteristics of the device. Transconductor probably made more sense (along with the FETs) but I don’t think they had a grip on network analysis then or had come up with that word. Ugh got a Laplace flashback then ... shudder.

Incidentally, one of Flemming's prototypes was featured in the science museum. I got a snap of it the other day:



According to the label it was actually donated by him personally.

Weird that everything we're doing started with that.
« Last Edit: August 17, 2019, 07:35:30 am by bd139 »
 
The following users thanked this post: mnementh, beanflying

Offline bsfeechannel

  • Frequent Contributor
  • **
  • Posts: 834
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37011 on: August 17, 2019, 07:40:19 am »
That maybe, but why did Flemming call them valves is the question then and being purely logical, might it be that he called them valves because of their ability to control the flow of electrons in a similar fashion to valves controlling the flow of a liquid or gas?

Fleming's 1905 US Patent application:

https://patentimages.storage.googleapis.com/23/09/50/6d4980acdfed12/US803684.pdf



Straight from the horse's mouth.
 
The following users thanked this post: bitseeker, bd139

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11610
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37012 on: August 17, 2019, 07:53:19 am »
There you go. Let’s all call them valves now  :-+ :-DD
 
The following users thanked this post: bsfeechannel

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 7431
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37013 on: August 17, 2019, 07:53:30 am »
We call vacuum tubes valves because they control the flow of electrons I guess [emoji16]

You call them valves because Flemming called them valves.
That maybe, but why did Flemming call them valves is the question then and being purely logical, might it be that he called them valves because of their ability to control the flow of electrons in a similar fashion to valves controlling the flow of a liquid or gas?

Well the first flemming valve was only a rectifier so I suppose that makes sense. I’m not sure it does for a triode etc. That’s a little more complicated due to the characteristics of the device. Transconductor probably made more sense (along with the FETs) but I don’t think they had a grip on network analysis then or had come up with that word. Ugh got a Laplace flashback then ... shudder.

Incidentally, one of Flemming's prototypes was featured in the science museum. I got a snap of it the other day:



According to the label it was actually donated by him personally.

Weird that everything we're doing started with that.
Well, I was only making a guess at its origin[emoji4] but surely with all valves / tubes if you don't connect the grids you are effectively left with a rectifier? It is weird when you look at the humble origins of what we do now I agree, look at the first transistor for example. Often the first anything is totally unrecognisable to today's version of it. [emoji848]

Sent from my POT-LX1 using Tapatalk
« Last Edit: August 17, 2019, 08:29:23 am by Specmaster »
Who let Murphy in?
 

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 7431
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37014 on: August 17, 2019, 07:59:38 am »
So it's official then, Fleming did call tubes valves after all, not a bad bit of deduction on my side there, get in! [emoji1787]

Sent from my POT-LX1 using Tapatalk

Who let Murphy in?
 
The following users thanked this post: bd139

Offline bsfeechannel

  • Frequent Contributor
  • **
  • Posts: 834
  • Country: 00
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37015 on: August 17, 2019, 08:09:55 am »
There you go. Let’s all call them valves now  :-+ :-DD

The Russian call them radio lamps. Dispute settled.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11610
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37016 on: August 17, 2019, 08:18:02 am »
Nyet!  :-DD
 

Online PA0PBZ

  • Super Contributor
  • ***
  • Posts: 4091
  • Country: nl
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37017 on: August 17, 2019, 08:33:32 am »
In Dutch they are called "buizen", that's tubes and I'm sure they are called just tubes in English too somewhere.
« Last Edit: August 17, 2019, 08:36:09 am by PA0PBZ »
Keyboard error: Press F1 to continue.
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37018 on: August 17, 2019, 11:08:35 am »
Vacuum tubes!  :P :P :P :P :P :-DD
An old gray beard with an attitude.
 

Online Brumby

  • Supporter
  • ****
  • Posts: 9240
  • Country: au
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37019 on: August 17, 2019, 11:18:54 am »
In Australia - they're valves.

But we still had VTVM's here - and we knew what they were.
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37020 on: August 17, 2019, 12:34:23 pm »
Speaking of VACUUM TUBES and VTVM's   :-DD...decided to start work on the Heath V-7A.

Looking pretty sad. Duff meter. Filthy cabinet and front panel. Going to completely break it down and spray paint the cabinet and clean the front panel along with replacing the meter.



First look inside. Very clean and appears well built. A filter cap and one wax tubular cap will have to go along with the selenium rectifier. No battery corrosion. Will check all the carbon comp resistors and the 9.1 ohm resistor in the ohms circuit that Gorillas always burn out when they try to do resistance checks with power on. Going to assume for now that the rest of the precision resistors are OK. They typically maintain their value.



An old gray beard with an attitude.
 
The following users thanked this post: edavid, Kosmic

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11610
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37021 on: August 17, 2019, 12:44:48 pm »
Looks pretty good that one. Whoever assembled mine did it with a fecking clothes iron or something  :palm:
 

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37022 on: August 17, 2019, 02:24:06 pm »
Well whoever owned this V-7A was no Gorilla.  ;D Other than the parts mentioned before which are automatic replace just one carbon comp is reading a little high. 3.9M vs 3.3M. So that will be added to change out list. The 9.1 ohm resistor that always seems to get burnt is reading 9.04 ohms.  8) No Gorilla here!  :-DD

Front panel has been cleaned along with the knobs. Case painted, currently drying. Going to reassemble it for now because the parts will need to be ordered.

Edit, I'll post a pix once I get it reassembled.
« Last Edit: August 17, 2019, 02:25:46 pm by med6753 »
An old gray beard with an attitude.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 11610
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37023 on: August 17, 2019, 03:00:13 pm »
Sounds great. If that’s the 3.3 meg on the input side of the 12au7 then that’s normally high. Not sure why but all of the ones I’ve had were high. Probably shitty carbon comps.

Just managed to bodge my Norcal 40A to get 5W out instead of two. Melted the collector choke to the board  :palm:. I am today’s gorilla  :-DD
 
The following users thanked this post: mnementh

Offline med6753

  • Super Contributor
  • ***
  • Posts: 4051
  • Country: us
  • Tek nut
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #37024 on: August 17, 2019, 04:52:12 pm »
The cosmetic portion of the V-7A restoration is done. The electrical portion pending receipt of replacement parts. A combination of an American VTVM and an English "Valve Voltmeter" meter. I hope it's a good relationship.  ;D My last relationship with an English redhead wasn't so good.  :scared:

Anyway.....that's the proper DC probe with the 1MEG resistor in the probe tip. And I took the top handle off my older V-5 VTVM. That guy is going into retirement and long term storage.


An old gray beard with an attitude.
 
The following users thanked this post: mnementh, bd139, Kosmic


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf