Test Equipment Anonymous (TEA) group therapy thread

[m k]

This one doesn't boot. Might have something to do with the missing masking tape on the ROMs. Sticker glue residue is still there but some ass removed the tape. Not sure if that's enough to corrupt the contents as there won't be much light inside the unit but maybe over time?

My guess is that it is what it is without stickers doing a thing, present or not.

[Ice-Tea]

Now that is a rats nest.. wow. Serviceability was not high on Marconi's requirements list it seems.

It never was!

Having just also serviced a 6200B: I agree. Like... a lot.

[Ice-Tea]

Me, about a year ago: "Oh, the crank is missing. Great opportunity to show of my fabrication skillzzz! Or maybe I'll have something 3D printed. I suppose I could also try to modify something off the shelf. On the other hand... Maybe I should...."



Me, now:



Works though:

[tggzzz]

Me, about a year ago: "Oh, the crank is missing. Great opportunity to show of my fabrication skillzzz! Or maybe I'll have something 3D printed. I suppose I could also try to modify something off the shelf. On the other hand... Maybe I should...."

KISS is good

[AVGresponding]

Me, about a year ago: "Oh, the crank is missing. Great opportunity to show of my fabrication skillzzz! Or maybe I'll have something 3D printed. I suppose I could also try to modify something off the shelf. On the other hand... Maybe I should...."

KISS is good

Can't stand Gene Simmons, myself

[tggzzz]

Me, about a year ago: "Oh, the crank is missing. Great opportunity to show of my fabrication skillzzz! Or maybe I'll have something 3D printed. I suppose I could also try to modify something off the shelf. On the other hand... Maybe I should...."

KISS is good

Can't stand Gene Simmons, myself

I presume he is a member of a popular beat combo with a name that isn't fully capitalised.

[44kgk1lkf6u]

I saw on American Ebay a Tek TDS7404 on auction currently at a price of $155.5.  That is rather cheap.  Do you guys recommend buying it?

https://www.ebay.com/itm/235810037931

Please point it out if this thread is the wrong place for this kind of questions.

[Ice-Tea]

You can probably sell the knobs on that thing for more than that.

You did notice it's broken, right? Also: now way that will be the final price.

[squadchannel]

if trigger chip is not dead, ah yes. Repairable maybe.

Since this is not a 1meg input, TekConnect probes or ordinary BNC probes cannot be used.
You need a dedicated and expensive conversion adapter, TCA-1MEG.
https://xdevs.com/review/tca_1meg/

So I won't buy it...don't need 4GHz...

[44kgk1lkf6u]

Also: no way that will be the final price.

I did not expect the price to grow like that.  How often does the price of something on Ebay multiply by 5 in the last day?

[abeyer]

Also: no way that will be the final price.

I did not expect the price to grow like that.  How often does the price of something on Ebay multiply by 5 in the last day?

If the price is "good" and there are more than a couple bidders, then it's almost certain to descend into bidding wars at the last minute.

[44kgk1lkf6u]

Bidding wars.  Do people bid more than once?  The highest bidder only pays the second highest bid.  So increasing the bid multiple times should have no advantage over putting in the highest price one is okay with paying just once.

[abeyer]

Bidding wars.  Do people bid more than once?  The highest bidder only pays the second highest bid.  So increasing the bid multiple times should have no advantage over putting in the highest price one is okay with paying just once.

The bidding history is public and you can see they do anyway: https://www.ebay.com/bfl/viewbids/235810037931?item=235810037931&rt=nc&_trksid=p4429486.m145235.l2565

[BILLPOD]

Bidding wars.  Do people bid more than once?  The highest bidder only pays the second highest bid.  So increasing the bid multiple times should have no advantage over putting in the highest price one is okay with paying just once.

Good Morning 44kgk1lkf6u, I agree and I enter the absolute highest I would pay and let Ebay increase the bids for me automatically.  If the price increases beyond what I would pay, then I was not meant to have it.  The last minute bidding wars make no sense at all.

[TERRA Operative]

Got the first OLED conversion done on one of my 3478A multimeters today, looks great, but there are a few things to improve on the next revision, detailed here:

https://www.eevblog.com/forum/testgear/hp3548-hp3457-oled-display/msg5704679/#msg5704679

[RolandK]

Bidding wars.  Do people bid more than once?  The highest bidder only pays the second highest bid.  So increasing the bid multiple times should have no advantage over putting in the highest price one is okay with paying just once.

Good Morning 44kgk1lkf6u, I agree and I enter the absolute highest I would pay and let Ebay increase the bids for me automatically.  If the price increases beyond what I would pay, then I was not meant to have it.  The last minute bidding wars make no sense at all.

This is one possibility. But humans are not rational, they tend to increase their bid, if someone outbids them. Therefor it is an advantage to bid the last second what you want to bid. So no one can increase anymore what he just bidded. ebay likes if you bid early - this drives the prices up. Eg. there is a bid of $100. You set $300. The first bidder increases and stops at $290, you pay $291. Else if you bid last moment, the first bidder can't increase his offer anymore. You pay $101 - or what others think what it is worth without seeing your bid.

[m k]

That's a confirmation bias.
You think others think like you.

If last moment is fixed you're forced to bid your highest.
If time remains few minutes after last bid you can milk the situation, here 'you' is relative.

[salvagedcircuitry]

I've been eyeing a E5062A or E5061b in decent shape as my first VNA for the lab. I came across a E5062A that turns on and seems to be working for $450. No cal kit, no adapters, just the instrument. Is that even worth it? It's an old instrument ~1994, runs windows 2000 and takes like 5min to boot. I'm thinking I'll hold out for a newer E5061b or some rohde and schwarz VNA equipment if any show up on the cheap

decisions decisions 
Thoughts and opinions welcome.

[BILLPOD]

This is one possibility. But humans are not rational, they tend to increase their bid, if someone outbids them. Therefor it is an advantage to bid the last second what you want to bid. So no one can increase anymore what he just bidded. ebay likes if you bid early - this drives the prices up. Eg. there is a bid of $100. You set $300. The first bidder increases and stops at $290, you pay $291. Else if you bid last moment, the first bidder can't increase his offer anymore. You pay $101 - or what others think what it is worth without seeing your bid.
[/quote]

Good Morning Roland, You make a good point that I hadn't thought of, and I thank you for that.  However, I am not going to go there at the last minute and
get involved in a bidding war.  The result that I may pay more than I want to
is exasperating.

[m k]

I've many times thought that since I'm already engaged to pay that much is it really so that I can't put there a bit more.
That can also continue few times, but then something happens and I start thinking that the thing is not worth even the previous bid.
Maybe I've missed some extra costs, but not necessarily, maybe the value just changed.

One local place uses a method where after last bid extra time is always 3 min.
There it's pretty clear when bidding war is possibly happening, but 3 min is also enough for consideration.

Completely other thing is to try manipulate others to keep price low, in my experience that is not going to happen, online is to big.
I'd say that if finally something is still cheap there just wasn't more interesting parties around, or you have valued the item differently.

[salvagedcircuitry]

A man with one clock knows what time it is. A man with two clocks is never sure.
GPSDO in the mail. Down the PPM rabbit hole.   

[unseenninja]

A man with one clock knows what time it is. A man with two clocks is never sure.
GPSDO in the mail. Down the PPM rabbit hole.   

Wrong order of magnitude. If you're going to go down the time nut rabbit hole, you need to start thinking in ppb.

 

[tggzzz]

A man with one clock knows what time it is. A man with two clocks is never sure.
GPSDO in the mail. Down the PPM rabbit hole.   

Wrong order of magnitude. If you're going to go down the time nut rabbit hole, you need to start thinking in ppb.

... and use concepts like "Allan variation " confidently and correctly 

[TERRA Operative]

A man with one clock knows what time it is. A man with two clocks is never sure.
GPSDO in the mail. Down the PPM rabbit hole.   

Oh! I'm working on some of these at the moment too! 

This one just got a complete overhaul. New electrolytic capacitors, new power switch (Original was smashed), all new jacks and plugs (old ones were bent and rusty), new input relays and a replacement transistor on CH1 that was faulty, New bumpers and handle, Opt010 OCXO, and 3GHz Channel 3 and a new VFD in the front panel.

My other one has a measurement error on the boot self test. It'll be put on the healing bench next.

[salvagedcircuitry]

A man with one clock knows what time it is. A man with two clocks is never sure.
GPSDO in the mail. Down the PPM rabbit hole.   

Oh! I'm working on some of these at the moment too! 

This one just got a complete overhaul. New electrolytic capacitors, new power switch (Original was smashed), all new jacks and plugs (old ones were bent and rusty), new input relays and a replacement transistor on CH1 that was faulty, New bumpers and handle, Opt010 OCXO, and 3GHz Channel 3 and a new VFD in the front panel.

My other one has a measurement error on the boot self test. It'll be put on the healing bench next.

Excellent work!

I'm eyeing a 3GHz Channel 3 module for mine too. I'm making a list of caps for my next digikey order so I can re-cap all 3 PSUs. I grabbed a sunon ~7cfm fan for my 53132a which is a little under the original ~10cfm fan, but this is not going to be running in a hot environment. I think it'll be fine. It's also ~12db instead of 28db. Crazy!