Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Looks brand new.  What chemical took the "10" off?

[mnementh]

s/Bo\ Derek/Christina\ Hendricks/

 

And where are YOU in all that sandwich...? 

Hendricks definitely has that smolder...  And a redhead. Loved her in Firefly. All the best kinds of trouble... 

mnem

[med6753]

s/Bo\ Derek/Christina\ Hendricks/

 

And where are YOU in all that sandwich...? 

Hendricks definitely has that smolder...  And a redhead. Loved her in Firefly. All the best kinds of trouble... 

mnem

A buxom bat shit crazy red head. Must resist.   

[bd139]

Looks brand new.  What chemical took the "10" off?

A plastic spudger designed to work on mobile phones from an iFixit tool kit and copious amounts of antibacterial kitchen cleaner

s/Bo\ Derek/Christina\ Hendricks/

 

And where are YOU in all that sandwich...? 

Hendricks definitely has that smolder...  And a redhead. Loved her in Firefly. All the best kinds of trouble... 

Never thought of that. I am clearly the ham in the middle 

Firely is religion in this house. In fact I'm sitting here with a firefly T-shirt on 

Edit: as much of a selfie as I'll ever do. T-shirt neatly fits in with the other comments made

[bd139]

A very nice 453 has appeared on eBay UK.  Buyer collects. 180 mile round trip for me. Worth it. I will fight anyone to the death on that one, if I don't spend all my moolah at Kempton

[tautech]

Troubleshooting (another) Anritsu MS8604A (8GHz SA). Tracked the problem to the front assembly, display probably. All the time I was working on it, a small bothered me. Couldn't quite pinpoint it but...

is that ? 

[Specmaster]

Could it be tin whiskers?

[0culus]

Another power meter joins the collection. 432A, but most importantly, this one came with a 478A thermistor mount. I also got the special old style line cord for the 431B, which enjoyed a successful power up with no dramatics.

[tautech]

Edit: as much of a selfie as I'll ever do. T-shirt neatly fits in with the other comments made

 

Just might fit mnem a lot better.   

[Specmaster]

I am considering it actually.

I've got a semi sketched out bench design I'm working on at the moment which may replace the Ikea thing I have at the moment. What with some criticism free freedom I can get another 3 feet of width you see

Some inspiration comes from here: https://stevenjohnson.com/workbenchphotos.htm

Wood + varnish + brass will come into it of course. It's better for the mind than metal and cheap laminates.

What are you going with, the 1946 type?

[Specmaster]

All done and cleaned.  Measuring an SLA there. Got rid of the 10. You can see some of it still at an angle but not enough to be bothersome. Looks like the original owner actually varnished the entire panel after labelling it so I might dismantle it in the future and go over it again with a light coat of varnish as well.



The shit scary thing is I had to scrape the label residue off the meter face with a flat blade screwdriver which is difficult as hell to do without scratching anything.

That really does look nice, of course if that does end up being screwed beneath a shelf, it will get used far more then if you have to dig it out each time you want it.

[bd139]

I am considering it actually.

I've got a semi sketched out bench design I'm working on at the moment which may replace the Ikea thing I have at the moment. What with some criticism free freedom I can get another 3 feet of width you see

Some inspiration comes from here: https://stevenjohnson.com/workbenchphotos.htm

Wood + varnish + brass will come into it of course. It's better for the mind than metal and cheap laminates.

What are you going with, the 1946 type?

Yes. Although it'll end up looking like the 1970 one 

That really does look nice, of course if that does end up being screwed beneath a shelf, it will get used far more then if you have to dig it out each time you want it.

Yeah that was one of the cool things about it. I'm starting to do a few valvey things here and there (currently after a heathkit SB-102 as well) so it'll be useful for that.

[Specmaster]

Never had a PayPal account and never will. For Ebay purchases I use a specific credit card. If things go south with the transaction I simply call the credit card company and let them duke it out.   

It's all about layers. I only use paypal with my credit card 

Edit: also Paypal UK office is walking distance from me. And there's a whoooole load of dog shit between here and there 

As an old established and trusted PP customer, I have many ways of using PP but my favorite way is to pay after delivery which means that I get 2 weeks free credit from them. If I use my Credit card, debit card or bank account or use any balance I have from my sales, I have no option but to pay them there and then, so more often then not I use the pay after option, allows my money to say in the savings account a bit longer, earning those few vital pennies more interest for me. 

[Specmaster]

Yes. Although it'll end up looking like the 1970 one 

That really does look nice, of course if that does end up being screwed beneath a shelf, it will get used far more then if you have to dig it out each time you want it.

Yeah that was one of the cool things about it. I'm starting to do a few valvey things here and there (currently after a heathkit SB-102 as well) so it'll be useful for that.

What 1970 one, I didn't find one in the book.

[bd139]

Link above rather than the book

[mnementh]

s/Bo\ Derek/Christina\ Hendricks/

 

And where are YOU in all that sandwich...? 

Hendricks definitely has that smolder...  And a redhead. Loved her in Firefly. All the best kinds of trouble... 

mnem

A buxom bat shit crazy red head. Must resist.   

Why? 

Edit: as much of a selfie as I'll ever do. T-shirt neatly fits in with the other comments made

 

Just might fit mnem a lot better.   

mnem
*original Browncoat-dwagon*

[Specmaster]

Replaced the Mosfet on the A109 today and everything was working fine for a few minutes then the protection relay clicked on, sound switched off and the input LEDs all flashed on/off which I think is a fault signal. Checked on the heatsinks and they were really warm and the Mosfet that failed and a new one installed was way to hot to touch for long, the other 3 were also very hot. Removed all fets, tested and they all tested OK so re-installed and tested the speaker terminals for the presence of DC and the left channel has a slow creep upto 3.5V before the protection relay cuts in. Back to diagnostics again 

[bd139]

Gah hate repairs like that. Good luck 

[med6753]

Yeah that was one of the cool things about it. I'm starting to do a few valvey things here and there (currently after a heathkit SB-102 as well) so it'll be useful for that.

An SB-102?  I thought you were done playing ham. 

[bd139]

Only the communicating with people bit. While there's people to mug, I'm still going to refurb stuff for my own enjoyment and sell it for a premium to pay for the test gear addiction

Also VHF SSTV, APRS, WSPR and futzing with microwave bands are still on. None of those require interacting with humans

[med6753]

Only the communicating with people bit. While there's people to mug, I'm still going to refurb stuff for my own enjoyment and sell it for a premium to pay for the test gear addiction

Also VHF SSTV, APRS, WSPR and futzing with microwave bands are still on. None of those require interacting with humans

Oh OK. Gotcha. Carry on. 

[mnementh]

Replaced the Mosfet on the A109 today and everything was working fine for a few minutes then the protection relay clicked on, sound switched off and the input LEDs all flashed on/off which I think is a fault signal. Checked on the heatsinks and they were really warm and the Mosfet that failed and a new one installed was way to hot to touch for long, the other 3 were also very hot. Removed all fets, tested and they all tested OK so re-installed and tested the speaker terminals for the presence of DC and the left channel has a slow creep upto 3.5V before the protection relay cuts in. Back to diagnostics again 

Desolder and lift the gate legs of all the FETs, power up with 100Ω resistors in place of the speakers. It may be easier to cut a slot in the pad to isolate the gate; if you do this, make the slot thin enough to easily bridge with solder when you're done diag-ing. If voltage creeps up on the outputs, then you have a FET leaking at operating voltage. Design of the amplifier determines whether that will be the source or drain of the FET; but you'll be able to identify the leaky FET by looking for the same voltage as at the speaker terminals.

If you're lucky, the new parts are okay and its some semi in the next stage up or even the one before that; these are often ICs but may be discrete. You'll be able to find the culprit by tracing back from the similarly creeping voltage on the gate pads of the finals; this is usually because the original failure cascaded excessive voltage up the amplifier stages.

Yeah, it's a total PITA. There's a reason most repair shops stopped fixing those damned things; hard to justify charging for hours of diag time on a stereo that can be replaced for $200-300 with new speakers and remote.

mnem
*tzzt*

[Specmaster]

Don't disagree, but for me its all about the satisfaction of a job well done and as long as I can flip it at the end and recoup my expenses then it's a win for me, kept me busy, increased my knowledge and exercised the old grey matter, at my age, thats important as I certainly don't want to lose the ability to think straight 

[mnementh]

Agreed; that's why I was passing on the hard-won knowledge of years spent fixing car stereo amps and bookshelf units like yours for fun & profit. This is the diag process I developed myself; it may be good, it may be bad... but it kept us in fuel and campground fees for several years when it was my primary source of income. 

Hope it helps you find the burnt bean that's stinking up your chili. 

mnem

[bd139]

And on that matter, this book, chapter "The Importance Of Fixing":

https://doc.xdevs.com/doc/_Books/Jim_Williams_The_Art_and_Science_of_Analog_Circuit_Design.pdf

(book contains pizza and tek guts)