Test Equipment Anonymous (TEA) group therapy thread

[ArthurDent]

A small part of my stove collection.

[tautech]

A small part of my stove collection.

The green one with the fold up legs and top wings is a lightweight Coleman right ?

[Kosmic]

Pffff,  why buy something from the last century when you can buy something modern ? 

This is mine. I put woods in it and it produce electricity while I cook my diner.



The stove actually charges an internal battery and the battery power the 5V usb port. So, you can charge your phone or gps with it.



Overall, it's working pretty well.

[Specmaster]

Looking at Svea stoves at the moment. Proper rollercoaster day. It was land rovers earlier. This is what happens when the TE listings are naff!

Just keep the cash in your bank, sooner or later something will turn up.

[ArthurDent]

A small part of my stove collection.

The green one with the fold up legs and top wings is a lightweight Coleman right ?

No. The one you're thinking of has the typical preheating tube that runs across the flame path and the waffle shaped flame plate. The one on the photo is the "stove, cooking, gasoline, M-1950, one burner" military stove with the Svea type tulip burner that will burn almost any fuel.

[tggzzz]

Now Boris is hospitalized! 

https://www.theguardian.com/world/video/2020/mar/27/i-shook-hands-with-everybody-says-boris-johnson-weeks-before-coronavirus-diagnosis-video

Since I'm not in a charitable mood and have just had enough wine that I cannot recognise poor taste...
https://newsthump.com/2020/03/27/government-updates-coronavirus-advice-get-used-to-idea-of-also-losing-unloved-ones/

[Specmaster]

When it comes camping stoves, the only ones I have any experience of are the ones made by Campingaz and I've had their small stoves, light and radiant heater and boy, do they throw out the heat?

[syau]

For good measure, you should double check the power supply. In most 53310A the caps in the power supply end up dying and leaking all over the place, causing a lot of damages.

Thanks. A little googling leads in that direction

I recapped mind using rubycon lzh series 

[Cerebus]

... Looking at Svea stoves at the moment. ...

I have a couple of Svea 123 backpacking stoves with the optional pump. One of them went the entire distance on the Appalachian Trail (3500Km) with me.

In the days when I used to regularly wonder off into the wilds I swore by my MSR whisperlite. Light, packed into any old corner, would run on anything  - it was best on coleman fuel (naptha) but it'd burn anything. Used to bang out a brew up in a couple of minutes once it was out and lit. Was quite capable of melting through a pan if you didn't keep an eye on it.

[nixiefreqq]

Thanks both. I have been on the end of a pressure valve event before with a different stove. Think it was a Coleman clone. Nearly lost my eyebrows. I’ve got a Trangia which is 3/4 my age and perfectly fine. Just really bloody slow and not very exciting

Get a Coleman Dual fuel and run it on unleaded gas. They have a few models that are dual fuel. Gas can be a bit stinky if you need to use it indoors in a power cut but boy does it pump out the heat !

Melt lead for fishing sinkers with mine. 

Edit to add
Model 533
Comes in a protective plastic 2 piece case.
https://www.coleman.com/all-camp-kitchen/camping-stoves/guide-series-compact-dual-fuel-stove/col_3000003654_pr/COL_3000003654

yes.  have backpacked with guys carrying those colemans.  fine stoves.  much easier to light in freezing weather than the old optimus or the svea. 

[VK5RC]

... Looking at Svea stoves at the moment. ...

I have a couple of Svea 123 backpacking stoves with the optional pump. One of them went the entire distance on the Appalachian Trail (3500Km) with me.

In the days when I used to regularly wonder off into the wilds I swore by my MSR whisperlite. Light, packed into any old corner, would run on anything  - it was best on coleman fuel (naptha) but it'd burn anything. Used to bang out a brew up in a couple of minutes once it was out and lit. Was quite capable of melting through a pan if you didn't keep an eye on it.

+1, used it (or prev v similar model) for the Overland Track in Tasmania, in early 1990s, always think of these stoves as 'chuffers'.
👍

[tautech]

Thanks both. I have been on the end of a pressure valve event before with a different stove. Think it was a Coleman clone. Nearly lost my eyebrows. I’ve got a Trangia which is 3/4 my age and perfectly fine. Just really bloody slow and not very exciting

Get a Coleman Dual fuel and run it on unleaded gas. They have a few models that are dual fuel. Gas can be a bit stinky if you need to use it indoors in a power cut but boy does it pump out the heat !

Melt lead for fishing sinkers with mine. 

Edit to add
Model 533
Comes in a protective plastic 2 piece case.
https://www.coleman.com/all-camp-kitchen/camping-stoves/guide-series-compact-dual-fuel-stove/col_3000003654_pr/COL_3000003654

yes.  have backpacked with guys carrying those colemans.  fine stoves.  much easier to light in freezing weather than the old optimus or the svea.

The 533 appears the only small liquid fuel stove Coleman make now. 
I got the 533 for the numerous day trips I did when the kids were small and they were mostly in my Landy so the plastic case gave it goot protection while rolling around in the back. 
A buddy had a bit smaller White Spirits Coleman with the fold out feet and he packed it a small pot/billy for protection. It was good too and we used it a few times in the snow when hunting.

In the days when I used to regularly wonder off into the wilds I swore by my MSR whisperlite.

I looked hard at one of those too when I got my Coleman but IIRC the Coleman put out more BTU's.

These days the Jetboil stoves seem to be all the go and now canisters have a better gas mix they work fine in low temps and the pot they come with doubles as protection.
https://jetboil.johnsonoutdoors.com/stoves-systems/micromo-cooking-system?id=13&_ga=2.36053476.536489148.1586133219-310495331.1586133219

[beanflying]

Bean, thanks for the heads up. I won the auction. 

  Good lot going to a good home. Sell two or three of them and by a bottle of Virus Relaxant

[med6753]

Bean, thanks for the heads up. I won the auction. 

  Good lot going to a good home. Sell two or three of them and by a bottle of Virus Relaxant

I had been browsing for older Tek probes with the PL-259 UHF connector for a while that were reasonably priced. Those 4 on the left are worth much more than the total price for all of them.

They will be used on the Type CA plug-in. I do have PL-259 male to BNC female adapters currently on it and they work but under certain circumstances they cause an "impedance bump" and distort the waveform. 

[worsthorse]

Damn. Gotta quit procrastinating by scanning ebay for stuff I-do-not-need-but-prefer-to-own. I bought another 3400A that I hope has a good thermocouple and found a couple of items to add to my sniping app.

The only project on my bench right now is the S38B, which I have dis-assembled and am now cleaning. I have most of the parts needed to do the restoration but for a multi-section cap, which is on order.  I am going to get this one finished and working before I start anything else.  The only real obstacle I see: I don't own a tube tester, so I can check for is filament goodness.

And, no, I am not going to buy a tube tester.   

Gonna buy two?     (Or three, so you have a tiebreaker?)

-Pat

lord, i hope not. i am just hoping to be able to make two outta one. the one i just bought cost less than a third what buying a NOS thermocouple would run, so its kinda like buying a lottery ticket.   

[worsthorse]

... Looking at Svea stoves at the moment. ...

I have a couple of Svea 123 backpacking stoves with the optional pump. One of them went the entire distance on the Appalachian Trail (3500Km) with me.

In the days when I used to regularly wonder off into the wilds I swore by my MSR whisperlite. Light, packed into any old corner, would run on anything  - it was best on coleman fuel (naptha) but it'd burn anything. Used to bang out a brew up in a couple of minutes once it was out and lit. Was quite capable of melting through a pan if you didn't keep an eye on it.

the whisperlite's was my go-to stove for years. four or five years ago, i bought an MSR wind burner (jetboil knockoff?) for one of the Nepal trips and i use it almost every time i go out now, as long as weight isn't an issue.

[Cerebus]

In the days when I used to regularly wonder off into the wilds I swore by my MSR whisperlite.

I looked hard at one of those too when I got my Coleman but IIRC the Coleman put out more BTU's.

Official figures are 3.5 minutes to boil a litre of water, as quick, if not quicker, than my kitchen stove I reckon. So about 100kJ/min aka 1600 watts (assuming 80ºC rise for the official figures). Not bad for something that literally fits into a, biggish, pocket and weights < 400gm.

[ArthurDent]

A while ago I picked up a 2 pot ceramic coated aluminum non-stick pot set with the MSR pocket Rocket in new condition at a thrift store for $2.99USD. And that price was before my 20% discount!

[0culus]

OK, new toy time, one that I've been waiting to find...

So inevitably I have far too many boxes that draw graphs of voltage-vs-time (scopes), too many that draw voltage-vs-frequency (spetrum analysers), but until today nothing that would complete the triumvirate by drawing frequency-vs-time (a modulation domain analyser MDA). I did buy an MDA cheaply last year, but it was effin heavy, junk and ended up in the skip – after I rescued an HP80811-60111 OCXO.

So I've been keeping an eye out for an MDA, but mostly they are £600+P&P (on my limit for a toy), often have dents, and even if a display is shown, the self-check screen shows a fault. Not interested.

So, when I noticed an Agilent 53310A where the owner showed it measuring things and also a clean self-test screen, I looked more closely. Since it had the high stability oscillator and third RF channel and was only £250+P&P, I jumped at the chance, even though that mutated into £350 and would take 4 weeks to get here. In the event, it arrived in 2 weeks

I remembered to change both mains voltage settings, and pulled off the lid, and the tube was still intact, so I turned it on, and bingo: I'm a happy camper.



So, what can you do with it? Obviously look at modulated signals up to 200MHz (ch A) or 2.5GHz (ch C), e.g. FM/PSK, or VCO transients as they change frequency. But, since it is fancifully and accurately described as a frequency microscope you can do much more interesting things than that.

The first task was to look at the output of my OCXO as it turned on and warmed up. The display isn't wonderful, but the top thin band shows a "panorama" of the entire f-vs-t graph captured over 800s, and the lower main section is a narrow window of that display.

The first thing to note is the number of digits in the frequency display, and that the vertical frequency scale is +-200Hz. The OCXO starts off 200Hz (20ppm) low, but after 400s it looks pretty close to nominal, but how close?




Or the same information presented as a histogram, vertical scale is logarithmic.



Looking at the histogram of the stable oscillator shows that (relative to the MDA's internal oscillator) it is 621mHz (62ppb low), with an RMS noise of 216mHz. Frequency microscope indeed



But, arguably more interestingly, even with a 200MHz input, it can measure sub-nanosecond risetimes, roughly equivalent to a 1GHz or faster scope.

The technique is to measure connect both channels A and B to the same input, channel A with a threshold at 10%, channel B at 90%, and measure the time difference between the two inputs with a resolution of 70ps.

I've previously measured my 74lvc1g14 step generator as having a risetime of ~250ps. The MDA indicates 370ps (and 200ps for 20%-80%). That's close since it is pushing the limits of the instrument; I need to sit down and fully understood the specification graphs in the manual.




And I'm sure it can do more strange and wonderful things

Nice! The 53310A is really a sleeper instrument. You wonder how the heck you ever lived without it. 

One of the things mine gets used the most for is as a counter. This might sound silly, but it makes a really excellent counter. With an external GPSDO ref, it makes tuning other frequency references a snap. And, unlike a normal counter, you can zoom way in on the signal for effective minute adjustments.

As an aside, if yours doesn't have the deep memory option installed, this is easy to add (you can still buy the SRAMs). You just populate the empty DIP sockets and move a couple jumpers. It noticeably improves the performance of the panorama function; also I believe it increases the depth of memory available for panorama, so you can use a larger time window.

[worsthorse]

So I am digging into the S38B. Nope, not TE, so I won't post more than this here, lest I incur some denizen-of-the-thread wrath...   

Here it is, out of the packing box. Manufactured, circa 1953:



I took a lot of photos of the dis-assembly (which raises the odds that the assembly process has some chance of success) which will get posted when I put up a thread.  But here is what the chassis looked like, out of the case:






There was some pitting and corrosion under all that dirt but it was not as bad as I feared. And here's what it looks like with six hours of cleaning later:






That smear at the bottom of the chassis is the shellac used to secure a label. That's also where the isolation transformer will be mounted when I get to that step.  The smear will be gone before I finish cleaning the top side tomorrow. Then I flip it over and start working underneath. That will involve mostly removing dirt while I inspect the wiring and parts I hope not to replace.  Some guys actually pressure wash stuff like this, others use a dishwasher.      Not my cup of tea.

[Cubdriver]

WH, don't be surprised if you find a bunch of high-value resistors disguised as tubular paper caps when you get to working on the underpinnings.  Beautiful job of cleaning it, BTW.

Good luck with your repairs.

-Pat

[mnementh]

So I've finished my fettling (this round at least) with the 3DP; it's currently printing another useless bit of faff to see if it is indeed working correctly. But this afternoon, while I was muttering to myself about just how much I love rewiring shit,  *~DING-DONG!!!~* goes the doorbell, and VROOOOM!!! goes the white Amazon van around the corner by the time I get there.

   Opening it up, I find the silver Creality extruder kit that was aspoda not gunna git here til the 30th. 

Checking, I find it is definitely the genuine CReality kit complete with their brand tattooed across it's backside; the same fit & quality as the one on my Tevo Tornado in storage.  And what's this...? A real live dead-tree printed destruction sheet, and one side actually in ENGLISH Chinglish?!?   

Certainly worth a dollar more than the crunky red one I sent back, if only for that.

I have lots of pics... not gonna bore y'all with but a few here once I'm all done. I have my new Ender 3 bits & pieces on the way; should be here in 2-3 days.

mnem
*toddles off to ded*

[med6753]

So I am digging into the S38B. Nope, not TE, so I won't post more than this here, lest I incur some denizen-of-the-thread wrath...   

Here it is, out of the packing box. Manufactured, circa 1953:



I took a lot of photos of the dis-assembly (which raises the odds that the assembly process has some chance of success) which will get posted when I put up a thread.  But here is what the chassis looked like, out of the case:






There was some pitting and corrosion under all that dirt but it was not as bad as I feared. And here's what it looks like with six hours of cleaning later:






That smear at the bottom of the chassis is the shellac used to secure a label. That's also where the isolation transformer will be mounted when I get to that step.  The smear will be gone before I finish cleaning the top side tomorrow. Then I flip it over and start working underneath. That will involve mostly removing dirt while I inspect the wiring and parts I hope not to replace.  Some guys actually pressure wash stuff like this, others use a dishwasher.      Not my cup of tea.

I don't see a power transformer which tells me immediately that's a series string receiver. I'll bet the audio output tube number starts with "50" and the rectifier starts with "35". The metal tubes probably start with "6" or "12" but utilize a split filament. And inline with the tube filaments probably a good sized power resistor. The tube filaments will add up to something less than 110VAC and the power resistor to make up the balance equaling 110VAC. 

 Given that it's a series string receiver one side of the AC line will be tied directly to the chassis. And I'll bet the line cord is still non-polarized. An isolation transformer is MANDATORY in order to safely work on that receiver. Depending on which way you plug in the line cord there will be 120VAC on the chassis unless an isolation transformer is used. 

Edit while I go......pulled up the schematic. Confirmed, series string receiver with one side of the AC line tied to chassis.

Also, you must make absolutely certain upon reassembly that no metal portions of the chassis are exposed on the cabinet which could shock the user. (except the antenna terminals which SHOULD be isolated)

Personally I hate that type of design because of the dangers but it was a cheap way to avoid the use of an expensive power transformer.
     

[salvagedcircuitry]

I've been spending time beefing up my bench. I just finished machining an insert for a very basic but useful magnifying lamp. Engine flywheels work surprisingly well as lamp bases . Pretty successful weekend project.

Overall, I'm pretty happy with the way it came out . Now what to do with all the desk space I made.... 

Here's the whole machining process:

Nicely done.  I thought from the initial pics it looked like a small South Bend.  I got an 8" three jaw chuck last year for my 10K; finally had occasion to use it a few months ago.  It looks rather disproportionate, but worked just fine.  Gotta love having a metal lathe on hand!

-Pat

Good eye! Thanks for the kind words . It's a South Bend 9in. It is definitely a treat to have a lathe on hand, especially when you need a prototype part in a jiffy. Originally, there was about ~11thou runout on my 3 jaw buck chuck. After some cleaning and re-adjustment of the back plate, I think I got it closer to 3thou and its been working great ever since. 

[Cubdriver]

I've been spending time beefing up my bench. I just finished machining an insert for a very basic but useful magnifying lamp. Engine flywheels work surprisingly well as lamp bases . Pretty successful weekend project.

Overall, I'm pretty happy with the way it came out . Now what to do with all the desk space I made.... 

Here's the whole machining process:

Nicely done.  I thought from the initial pics it looked like a small South Bend.  I got an 8" three jaw chuck last year for my 10K; finally had occasion to use it a few months ago.  It looks rather disproportionate, but worked just fine.  Gotta love having a metal lathe on hand!

-Pat

Good eye! Thanks for the kind words . It's a South Bend 9in. It is definitely a treat to have a lathe on hand, especially when you need a prototype part in a jiffy. Originally, there was about ~11thou runout on my 3 jaw buck chuck. After some cleaning and re-adjustment of the back plate, I think I got it closer to 3thou and its been working great ever since. 

...now if I could just get my paws on a Bridgeport for the garage...

-Pat