Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 14782773 times)

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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92250 on: June 12, 2021, 08:49:30 am »
I guess Uncle Joe and Boris the Spider got along just swimmingly walking together shaking each other's dick. Not sure which one looks more the dumb ass. Granted, anything is better than Chump but Joe has issues too. First and foremost he's practically senile.  :palm:


Can you hold him over for violating quarantine?  Much appreciated.  ;D And when it comes to rules you should know by now that it's "do as I say, not as I do".   ::)
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Offline beanflying

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92251 on: June 12, 2021, 08:57:47 am »
Lets not forget the SELF important Tennis players have been tripping around the world spreading COVID since January (bitching about quarantine while they went  :--) along with the Olympics and F1 and ..... Also lets not forget those living in Countries where COVID is still more or less unchecked then shouldn't be crossing any international borders. USA to Mexico among others and UK to Spain etc. travelling without any quarantine of any sort.

At 'some' stage regardless of 'some' risk 'some' sort of normal does need to come back.
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92252 on: June 12, 2021, 09:05:00 am »
And now for something completely different, as you might know, there is a little something going on in Cornwall UK, called the G7 Summit and there is one nation that will more than likely be lecturing the other member nations about the need to tackle climate change, just a shame that they don't lead by example, who is it, why it's the USA, who else. There has been an insane amount of transatlantic flights undertaken by hoards of C17's and C5's and presidential planes along with the relocations of loads of KC135, Hercules and Ospreys into Newquay, Brize Norton, Stanstead, Mildenhall, Lakenheath, Fairford and Northolt. I'd hate to think about the carbon footprint of that operation so far, which has one more airport to add to its list on Sunday, Heathrow, when the President departs for NATO meetings and the First Lady returns to the White House.

That said, it has been a dream for my son and I with all the photographic opportunities. Wednesday we were at Mildenhall hoping to catch a busy day of operations, but we were disappointed as it was in a lockdown in preparations for the arrival of AF1 and support aircraft amid a massive security operation all around the airfield with photographers lining the road outside the base being moved on by police. That said, however, there were 2 locations we were allowed in, not ideal as it meant shooting through a chain link fence but for those interested people here are a couple of photos I managed to get after waiting around for almost 10 hours.

I will be trying to get some better shots of these departing Heathrow on Sunday if we can find a location that we will be allowed to shoot from.  :palm:

After Sunday, all of those aircraft movements and support flights on the C5's and C17's will be reversed again in order to return all the cars, helicopters etc, back where they came from.

I'm sure they're all going to talk about how everyone else needs to reduce their carbon footprint after burning tons of jet fuel to get there and back.

Did you see the Government of Canada plane that brought Justin "Now is not the time to travel" Trudeau there?

Rules for thee but not for mee on all sides at that shindig, that's for sure.
No I never saw any other planes, only the USA ones. I think that all the other heads of state flew directly into Newquay airport and also accepted the transportation to and from the various locations that we provided them while they are here.

Its only Biden that has been invited by the Queen for afternoon tea at Windsor Castle on Sunday before he heads of for NATO talks so as a result he has had to have so many plane movements to minimize his exposure on the ground so to speak. The USA is also the only nation to have military bases here in the UK, hence his visit to RAF Mildenhall in order to address many of the staff from other bases at the same time.

But you're right, it is all about one rule for them and their wealthy mates and another for me and thee. :palm:

Hey, last century when we had to come over twice to bail you guys out did we just show up in a row boat?   :P :-DD
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92253 on: June 12, 2021, 09:06:58 am »
Lets not forget the SELF important Tennis players have been tripping around the world spreading COVID since January (bitching about quarantine while they went  :--) along with the Olympics and F1 and ..... Also lets not forget those living in Countries where COVID is still more or less unchecked then shouldn't be crossing any international borders. USA to Mexico among others and UK to Spain etc. travelling without any quarantine of any sort.

At 'some' stage regardless of 'some' risk 'some' sort of normal does need to come back.

Over here mask restrictions have been for the most part lifted in public places such as stores, restaurants, etc. But kids in schools must still wear masks.
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Offline VK5RC

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92254 on: June 12, 2021, 09:18:46 am »
Apologies, Grump mode on
Re covid and bizarre exemptions - the one that gets my goat is the football exemptions - even then the lads didn't follow rules - well who would have predicted that!
And you can stick multi thousands in a stadium. But you can't fly home for your brothers funeral (happened to a work colleague).
Recently our state built its first decent sized sports stadium and from certain angles its a lot like the colliseum - I am waiting for a vomitarium and they flood it and have mock sea battles.
Our society is losing sight of its priorities.
Grump mode off.
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Whoah! Watch where that landed we might need it later.
 
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92255 on: June 12, 2021, 09:44:11 am »
got an interesting thingie on the bench.

I dropped a mainboard by mistake. Eff my luck. One of the main SMD caps (120 u 35V) tore off. It left the pads undamaged.

Unfortunately I do not have my scope, kapton tape, microscope, rework stuff with me, just a TS100 (lead battery powered) which I used to attach a radial 120u cap.
The board starts up for about 30 seconds, goes thru self test and then powers down. So I am wondering: what else broke. Could be that the BGA CPU package suffered, could be that the cap I soldered in is not up to specs.

I got a replacement SMD 120u low ESR cap from Panasonic and I will try to solder it to the pad when I have my rework equipment with me. With the battery powered TS100 I just cannot do it. Will probably need some solder paste, flux, cleaning of pads and hot air while protecting the rest of the board with kapton tape.

Bloody hell.

In other news, fixed a Vectrex game console (manufactured in 1982). Controller and sound functional again.

A dropped board likely means some BGA solder damage, probably needs reflowing...   :--
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92256 on: June 12, 2021, 09:46:56 am »
Do I need to send you some connectors now? When you say 'internal interconnects' SMA PCB jacks would be probably ok - together with some SMA cables? But RCA? puh-leeze!

In any case, depending on how refined I make my design, I might need as many as 20 or more plug and socket pairs.

When I make multiple copies of a board, or need cheap interconnects for external or internal connections, there's two very economical and convenient resources many people don't know aboot:

   https://www.amazon.com/s?k=cctv+pigtail

These 5.5mm x 2.1mm coaxial DC power pigtail pairs are crazy cheap for what you get; typically $10-20 for 10 pairs. They come with 22-16ga wires, in red/black or plain black sheath, with or without 1/4 turn locks. There are also variants with screw terminal blocks on male/female pairs of Coaxial DC connectors; you'll see them as well in the above search.

   https://www.amazon.com/s?k=lipo+Balance+extension

When I need lots of inexpensive, easily human-handled interconnects between PCBs inside a project box, one of my favorite sources is LiPo balance extension cables. These usually come in 5-10 packs for $10-20, in 3-7 conductor versions with 150mm-250mm length, premade with JST-XH socket on one end and plug on the other. The nice part is decent-heavy 22ga silicone wires which are a joy to work with, as they don't melt away like bubble-gum if you dare to solder the wires directly.  :-+

If you can spare the time to strip the wires off the socket, they can go straight to a PCB and solder the other end. Or cut the socket end off and crimp a new JST-XH plug to make a plug-plug interconnect in half the time. Or just cut the extension in half and solder wires directly to the board at both ends with or without ferrules or whatever other strain relief as you see fit. ;)

Cheers,

mnem
'lectronic Legos... ;)

Those aren't screened cables, which this projects demands. I've ordered a shit-load of cheap "gold" RCA chassis sockets, shopping around for some plugs now as I don't have enough of those either.
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92257 on: June 12, 2021, 10:00:30 am »
@AVG Most likely.
 

Offline SilverSolder

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92258 on: June 12, 2021, 12:02:12 pm »
Do I need to send you some connectors now? When you say 'internal interconnects' SMA PCB jacks would be probably ok - together with some SMA cables? But RCA? puh-leeze!

In any case, depending on how refined I make my design, I might need as many as 20 or more plug and socket pairs.

When I make multiple copies of a board, or need cheap interconnects for external or internal connections, there's two very economical and convenient resources many people don't know aboot:

   https://www.amazon.com/s?k=cctv+pigtail

These 5.5mm x 2.1mm coaxial DC power pigtail pairs are crazy cheap for what you get; typically $10-20 for 10 pairs. They come with 22-16ga wires, in red/black or plain black sheath, with or without 1/4 turn locks. There are also variants with screw terminal blocks on male/female pairs of Coaxial DC connectors; you'll see them as well in the above search.

   https://www.amazon.com/s?k=lipo+Balance+extension

When I need lots of inexpensive, easily human-handled interconnects between PCBs inside a project box, one of my favorite sources is LiPo balance extension cables. These usually come in 5-10 packs for $10-20, in 3-7 conductor versions with 150mm-250mm length, premade with JST-XH socket on one end and plug on the other. The nice part is decent-heavy 22ga silicone wires which are a joy to work with, as they don't melt away like bubble-gum if you dare to solder the wires directly.  :-+

If you can spare the time to strip the wires off the socket, they can go straight to a PCB and solder the other end. Or cut the socket end off and crimp a new JST-XH plug to make a plug-plug interconnect in half the time. Or just cut the extension in half and solder wires directly to the board at both ends with or without ferrules or whatever other strain relief as you see fit. ;)

Cheers,

mnem
'lectronic Legos... ;)


+1 for the JST-XH balance cables.   They have standard 0.1" pin spacing so work great with breadboards as well.  They are even cheaper on eBay, you can sometimes pick up packs of 50 for very little money.  I can't even remember what I used to do before getting them...  suppressed bad memories! :D



 
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92259 on: June 12, 2021, 12:13:27 pm »
Do I need to send you some connectors now? When you say 'internal interconnects' SMA PCB jacks would be probably ok - together with some SMA cables? But RCA? puh-leeze!

In any case, depending on how refined I make my design, I might need as many as 20 or more plug and socket pairs.
Still not impossible - but only PCB jacks. I will recount them on tuesday.
 

Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92260 on: June 12, 2021, 01:59:11 pm »
Hey, last century when we had to come over twice to bail you guys out did we just show up in a row boat?   :P :-DD

You didn't bail us out, we just graciously invited you because we thought you would like to experience an overseas war where you were on the winning side for once. Anyway, we all know that your real reason was to get a cup of tea that was worth drinking.
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92261 on: June 12, 2021, 02:08:15 pm »
Hey, last century when we had to come over twice to bail you guys out did we just show up in a row boat?   :P :-DD

You didn't bail us out, we just graciously invited you because we thought you would like to experience an overseas war where you were on the winning side for once. Anyway, we all know that your real reason was to get a cup of tea that was worth drinking.

Nah!

They saw a war footing would put the depression behind them, could make a profit, and take over as leaders of the free world. They've been complaining about the obligations that come with the latter ever since  >:D :)
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92262 on: June 12, 2021, 02:38:08 pm »


You mean that decent tea you stole from the Chinese...?  ;)

mnem
« Last Edit: June 12, 2021, 02:40:57 pm by mnementh »
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92263 on: June 12, 2021, 04:29:42 pm »


You mean that decent tea you stole from the Chinese...?  ;)

mnem

The very same one that you all threw into Boston Harbour, didnt you lot understand that you cannot brew a nice cup of tea with cold salt water, it has to be boiling, fresh water  :-DD :-DD
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92264 on: June 12, 2021, 05:20:45 pm »
You mean that decent tea you stole from the Chinese...?  ;)

We didn't steal it. We didn't have enough silver bullion for their taste, but they accepted opium in lieu of that :(
« Last Edit: June 12, 2021, 05:24:05 pm by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92265 on: June 12, 2021, 05:21:13 pm »
You mean that decent tea you stole from the Chinese...?  ;)


We didn't actually steal tea from China, we bought it from them, with opium. (We weren't the only ones, FDR's grandfather smuggled opium to China.) The good tea was stolen from India, along with the rest if the country, the other stuff we shipped to the other colonies. Then we actually started growing our own. OK, so we occupied Kenya to do it, but Kenya was also good for growing coffee. Why do you think we hung on to Kenya until 1963, but let the Indians have their country back in 1947?
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92266 on: June 12, 2021, 05:57:18 pm »
Not that having the world's largest navy of privately-owned warships... err, defensively-armed cargo ships helped in any of those negotiations over the centuries... no, no, no... ;)

mnem

heh-heh-heh-heh-heh... >:D
« Last Edit: June 12, 2021, 06:00:44 pm by mnementh »
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92267 on: June 12, 2021, 07:15:03 pm »
Discordant sounds are ringing across the interweb
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Offline Runco990

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92268 on: June 12, 2021, 07:57:37 pm »
One scope from HP's first all purpose digital series must be allowed, or ...  :-//
I mean, from the pre floppy era.   :-)

Anyway, I had to rescue this 54504 400 Mhz guy with handbooks and in perfect shape for about 175 Euros including shipping.

First start: fan running, black screen
Second start: scope running ... into some kind of error after a while and asking for restart
Third start: scope running, all self tests passed

Voltage measurement seems to be a bit low. Shoud be 500 mV but shows 485mV.

1) I wonder, if RAM/battery might need replacement

2) What would be a matching probe within a reasonable budget?
Maybe it was a mistake to grab a 400Mhz model with an input capacity of 7pF, as most cheap probes starts with 10pF compensation.

If I recall.... THAT scope has a Dallas chip battery in it.  I have owned these, and they are ok... but can't actually hold a candle to a modern one.  However, they are just beautifully built! 
Remove the NVRAM chip and replace it, or do the external battery mod to it.  Put in a socket while in there, check for leaking capacitors on the power supply (common) and then let it do a re-cal.

Use a HP probe rated for the scope. 

 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92269 on: June 12, 2021, 08:11:42 pm »
Discordant sounds are ringing across the interweb

Yep.
Discord is open with all the usual suspects. :)
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92270 on: June 12, 2021, 11:27:55 pm »
Discordant sounds are ringing across the interweb

Yep.
Discord is open with all the usual suspects. :)
Oops, missed again, just been so dammed busy of late with all the G7 aircraft movements to try and snap along with all the other aircraft related events that my son wants to cover while the weather has been cooperative. Just a bloody shame that the information has not been the best it could have been, resulting a lot of wasted time waiting for events to happen, and then when it does, the sun does not cooperate with its angle, or goes behind a cloud, rendering photography pointless unless you want to see black shapes against the background  |O

Tomorrow, its off to Heathrow for the Presidential flights etc, later in the weeks off down to Oxfordshire to pick up a piece of trim for the car. A piece that was ripped from the car by one of those automatic car washes, a piece that the makers want a small fortune for, without painting it to match the car and fitting  :palm:

I have even missed out on some great bits of kit on eBay because of all of this G7 mularky but its coming to an end soon  :phew:
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Offline Brumby

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92271 on: June 13, 2021, 01:29:50 am »
Discord wasn't even on my radar today... Picked up a bug and it's making me feel rather ordinary.

While I was pretty certain it wasn't COVID, I got the test done, just to be sure.  That came back negative - but they also did a couple of other tests, because I was sick.  Turns out I have RSV.   Bleahhh


Oh well, it could be worse.
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92272 on: June 13, 2021, 07:31:41 am »
Discord wasn't even on my radar today... Picked up a bug and it's making me feel rather ordinary.

While I was pretty certain it wasn't COVID, I got the test done, just to be sure.  That came back negative - but they also did a couple of other tests, because I was sick.  Turns out I have RSV.   Bleahhh


Oh well, it could be worse.
Still sounds bad enough, get well soon.
Who let Murphy in?

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Online Peter_O

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92273 on: June 13, 2021, 09:38:07 am »
One scope from HP's first all purpose digital series must be allowed, or ...  :-//
I mean, from the pre floppy era.   :-)

Anyway, I had to rescue this 54504 400 Mhz guy with handbooks and in perfect shape for about 175 Euros including shipping.

First start: fan running, black screen
Second start: scope running ... into some kind of error after a while and asking for restart
Third start: scope running, all self tests passed

Voltage measurement seems to be a bit low. Shoud be 500 mV but shows 485mV.

1) I wonder, if RAM/battery might need replacement

2) What would be a matching probe within a reasonable budget?
Maybe it was a mistake to grab a 400Mhz model with an input capacity of 7pF, as most cheap probes starts with 10pF compensation.

If I recall.... THAT scope has a Dallas chip battery in it.  I have owned these, and they are ok... but can't actually hold a candle to a modern one.  However, they are just beautifully built! 
Remove the NVRAM chip and replace it, or do the external battery mod to it.  Put in a socket while in there, check for leaking capacitors on the power supply (common) and then let it do a re-cal.

Use a HP probe rated for the scope.

Thx, Runco990!
I've bought this one to play a bit with the first fully digital generation and user interface design. For every day measurement  there is a Siglent 2000x plus available. Not that optimized an interface compared with HP ;-)   but plenty of functions for my hobby use.
With your keywords I searched the forum again and found: https://www.eevblog.com/forum/reviews/defective-hp-54504a-nvram-substitute/msg91979/#msg91979
I didn't know, that the scope is capable of self calibration. So I can check, if voltage accuracy improves, before doing the RAM change/mod.

Yea, HP probes would be the right way, but maybe a little out of budget for this vintage side line. One new N2889A or N2890A would be the price of the scope. But maybe I'm lucky 2nd hand.

 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #92274 on: June 13, 2021, 12:03:56 pm »
Back working on the Type 547 and thanks to some pictures provided by Oculus it looks like I found something around C642A/B which are the filter capacitors for the -150V reference.

This is how my C642A/B is wired. And you can clearly see that some Gorilla has been in there by all the melted wires. And seeing that raised my suspicions and it appears I may be right. It's screwed up.



Here is how C642A/B is wired on Oculus' functional Type 547. There is an additional white with possible colored strip going to side of cap that's tied to ground. I can't see what wires are attached to the lug immediately to the left of grounded lug because that heavy white is covering it. But clearly it doesn't match mine.



Oculus, I hate to ask this but I need 2 pieces of additional info. Does the white wire down against the chassis and going to that grounded cap lug have a color stripe on it? And the lug covered by that heavy white wire. What are the colors of the wire(s) going to that lug? I know it's a PITA because you have to flip the 547 back on it's side to see the wiring.

Edit....in studying this more it appears that the difference is those heavy white and yellow wires. They don't appear anywhere on my wiring harness and could be a running change made by Tek and probably unrelated to the PSU issue. But I still need to know the color of the wires under that hidden lug.     

2nd edit.....can you give me a clue as to what those white and yellow wires are for?
« Last Edit: June 13, 2021, 01:46:23 pm by med6753 »
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