Need help repairing couple 'scopes (different faults)

[fezder]

decided to buy this one, thanks for the tip!
**broken link removed**

 

[KeepItSimpleStupid]

Here's the manual for mine: https://www.ptouchdirect.com/ptouch/umpt1400.html I know it was less than $100 USD.

It uses the TZe style tapes which are inexpensive if you but them online, BUT expensive if I buy locally. See: https://www.ptouchdirect.com/categories/ptouch/tze-tapes.html

See: https://www.ptouchdirect.com/ptouch/tz_tape_specialty_guide.html for tapes

Mine is super easy. It has like symbols of a telephone or ground symbols etc. It can do 3 lines on 1/2" tape.

Most of my labels are on the high strength 1/2" black on white tape.

==

This https://www.ptouchdirect.com/ptouch/new_pte500.html guy prints on heat shrink. The stuff that was important to me was # of lines, and cable labeling.
The only drawback of mine is that it wastes about 1/2 to 3/4" of tape for each single label it prints. If you don't wait long enough before you cut, you get "cutter error".
It's not a QUERTY style keyboard.

I'm surprised they don;t show the symbol list.

===

Mine could be very similar to this one by Burndy: https://www.bradyid.com/bradyid/cms/contentView.do/6398/featured.html

 

[KeepItSimpleStupid]

That one has a 1/2" and 2 line limitation which isn't too bad. Occasionally, I print 3 lines.

 

[fezder]

got parts, replaced them (except opamp) so far no fault

 

[fezder]

got parts, replaced them (except opamp) so far no fault
oops, douple post...ps: that p-touch thingy is quite handy, thanks for the tip!

 

[KeepItSimpleStupid]

Well, Fez. I'm not surprised that it's working, but I am surprised with the repair. It's up there with the "intermittent fuse" which I have seen twice. What was bugging me, was the power supply had no evidence of current limiting, yet you were loosing 12V.
I got lucky suggesting freeze spray on the bridge. I could see the point of going further until the supply was fixed. So, the puzzle was is it the supply or something loading the supply. No current limit through me a curve.

I said earlier that adding TVS diodes on the secondary(s) might be a good option. Your call.

I just got a broken Keithley 485 autoranging picoammeter from ebay for like $90.00 USD delivered. I ordered the suspect $0.25 USD part to fix it. One range read zero, All the other's overload. My finger made the digits jiggle in the nA range. So, one part for sure, possibly two. I'll bet if I snip the part, all of the other ranges will work. The front connector was loose which took out a FET,

The current source I need to work on has more issues. Parts in hand. This one supposedly was fixed and broke again, the seller said and he didn't want to deal with anymore.

The voltage source works with the IEEE board disconnected, so there is a direct short.
Either the 160B voltmeter or a Keithley 480 picoammeter needed a converter chip.
I have frequency counter that needs some tact switches replaced - I have them in hand.

I might get more fixed, because I have to dig out the soldering/desoldering station soon.

Then I have some scopes to work on. A Dallas clock chip replacement that also holds calibrations. So, it's remove (no socket), read it, and program it into another chip. Put a LP socket on the board and hope for the best. The floppy drive will get converted to USB. Then there are two battery scopes, the TEK 211 and TEK212. To get both working, I would need a 3D printed part. Taking a course and doing it locally is an option, but first it has to work electrically. One scope needs battery pack holders which act as spacers for the PCB.

==

This week, I was tracking down how to make a high temperature insulator for an isolated NC switch on a 1/4" phone jack. I asked a friend, but he wanted to do it. It's his lathe. So, anyway after his failures and my success at home, I can use a plastic thread forming screw in a piece of Macor (Machineable ceramic) or for reduced temperature service (450F), I can tap a piece of PCTFE. https://en.wikipedia.org/wiki/Polychlorotrifluoroethylene. It has a slight impact load, but I'll try the ceramic first. Titanium washers will reduce the thermal conductivity from the wall to the part itself. Fun little home project.

Now, my wireless mouse died. So, I just ordered USB surge protectors and a replacement on ebay. The receiver side blew in the last one.

==
Glad you liked the label maker.

 

[fezder]

sure, those tvs-diodes sound good, no bad thing about extra-protection no?

 

[KeepItSimpleStupid]

I think, two Bidirectional 1.5KE30A diodes on the 16-0-16 VAC secondary would work. One on the 16-0 and one on the 0-16 part.

 

[fezder]

Bidirectional 1.5KE30A

goodie, those are available locally (as well as other TVS's). pretty cheap too, only 0.6€ incl VAT. so, if i got it right, TVS ''closes'' when voltage rises too high, and protects circuit parallel to it, leading transient to elsewhere?

 

[KeepItSimpleStupid]

A TVS basically is a Zener diode optimized for brief over voltages. They come in unidirectional and bi-directional varieties. You would hope that the Zener absorbs the surge and if it doesn't the primary fuse pops, The secondary COULD pop.

 

[fezder]

i have those tvs's now, what would be the best way to install them? i'm thinking about soldering them to pcb, orto wire them to connector (sounds better idea....)

 

[KeepItSimpleStupid]

You might try putting stranded wire pigtails on them? Splice into the wires going to the plug? Busy these these days. and a particularly nasty headache earlier in the week. Temperature rose by 20 degrees in 12 hours. I hadn't seen that possible trigger before.

 

[fezder]

ouch, i got too headache today, nasty things :S but tvs'
s now installed, just need to make appropriate markings of this addition. thanks for help, again!

 

[KeepItSimpleStupid]

Yep, I think I recently fixed the Zero resistance ammeter. So, I marked "Qx replaced 12/2014" with the labeler. I still need to do the final test.

 

[tvtech]

Pffttt..you awake Buddy?

What's happening Fez?

Regards,
tvtech

 

[fezder]

'been re-organizing my 'shop, post some pictures at blog today and other stuff too comin' up!

 

[throbscottle]

Hey TV - is that really you in yoiur profile pic? You looking Niiiiiccee...

 

[tvtech]

Hey TV - is that really you in yoiur profile pic? You looking Niiiiiccee...

Yip that's me throb

I have always been beautiful but the hair cost me a fortune....I was forced to import it....
Being naturally bald does not get you into the finals of competitions like this one.

Crowds like hair. Lot's of it.

So, a girls gotta do what a girls gotta do

I love my new Avatar

 

[fezder]

It uses the TZe style tapes which are inexpensive if you but them online, BUT expensive if I buy locally

ok, mine laberel uses same tapes, where do you buy them? i'm trying to find good price-shipping ratio

 

[throbscottle]

I have a P-Touch 1000 (I think), and TZ tapes are dead expensive, even purchased online. However, I've tried using a copycat tape (off eBay), much cheaper, and so far it's stayed stuck (labels have been on over a year). Don't expect TZ high performance characteristics, but then I don't need them.