Your daftest mistakes??

[davegsm82]

Originally Posted by Nickthedentist

What a sad story, Dave, I'm surprised you didn't give up on TV repair altogether!

It was almost the end! I'd never known such disappointment until that point.

Fortunately I found a very similar donor set a couple of days later but oddly it didn't use the Mini-Neck tube, instead it had the older wide neck. Upon fitting (including tube base board) it needed some fettling of the Focus, A1, height and width but it was otherwise ok again.

My Mum used that TV until quite recently, in fact I can't remember her getting rid of it, so it may still be sitting there in her wardrobe. Will have to ask next time I'm over.

Dave.

[Tim]

Too many to list. They would require an entire thread!

I do remember these classics, both of which happened at least 20 years ago.

I was working on a portable telly, and in accordance with common practice had the TV plug in my pocket so i would not plug it in, in-advertently. Unfortunately I forgot this and got up to get a component from my storage draws on the other side of the workshop. I dragged the telly, and AVO8(which was attached at the time) off the bench. The telly landed on the chair(fortunately as it was repair for a prosprective girlfriend.......) but the AVO hit the floor and was never the same again. I did complete the repair and she was very pleased.
Now I have a small carboard box covered in red tape and warnings, in which I place the plug.

I also bashed the top off a Pen453DD, while getting a Murphy AD32 chassis out of the cabinet. The said valve was in an adaptor, adding to the height and it caught on the top rear cover fixing bracket.



A friend of mine did a good one when he was working for BT. He was up a pole working on a customers line, and as is commonly the case he "ran out of hands". He clipped his test telephone onto a drop wire and it promptly slid down the wire and ended up mid span over a busy road. He unhooked the dropwire wire, but unfortunately he let go when climbing down, and had to watch as his test phone hit the road and smashed into a myriad tiny peices.

[Tim]

And the time when I drilled a hole for a cable, out through a customers walls with a 1 metre long drill (they were thick walls) and into a water butt!
Luckily they saw the funny side and put the kettle on while I fixed it with a small screw and nut and a couple of tap washers.

[Nickthedentist]

Tim,

I once drilled a hole from the outside in, to save damaging the brickwork; after all, a little plaster repair on the inside would be quick and easy. Somehow, my calculations turned out to be completely wrong, and the hole ended up in completely the wrong room!

N.

[newlite4]

Mid '70s, I would have been 14, I had bought a nice Philips Superinductance at a jumble sale for a pound (those were the days!). Some months later, the stack of radios was approaching five feet tall, with the Philips on top. A slight nudge and the lot went over . The barretter in the Philips had failed through shock so I bypassed it. On switch-on the mains hum grew louder and louder until the heater in the output pentode blew open circuit . In those days, it was practically impossible to ontain parts for "unwanted old radios" - not like today with the wealth of available parts! The set was given away a few years later. Ho Hum.
Neil

[threeseven]

Originally Posted by high_vacuum_house

Good evening,
I have had a really daft mistake today whilst at work. I was fault finding on a diesel electric railway loco which has a high power V16 engine driven 3 phase alternator which is then rectified with a huge bridge rectifier to DC between 920v and 2500v depending on the exitation current. Thyristor invertors then create a 3 phase supply from this to power the traction motors.

There was a fault with the main 3 phase bridge rectifier which I decided to test for shorts. It was disconnected and meggered with an electronic type megger at 1Kv It did not occur to me at the time for some reason that the slowly rising insulation resistance was a capacitor across one of the diodes charging up to 1Kv !! After satisfying myself there was a fault with this rectifier I then started to unbolt the clamps which hold the module in. I touched the still charged up terminals of the rectifier which made me jump backwards violently with my back hitting the safety handrail along the walkway of the locomotive. The force of hitting the handrail has given me a very bad back and I am currently in a lot of pain and can hardly bend down. Now having learnt the hard way that there are capacitors in the brige rectifier module!!

Christopher Capener

picture of the Siemens DI8 locomotive that are currently working at Redcar steelworks

That made me gasp! Be VERY thankful you're still with us!
Back when I worked for CES Leeds one of the microwave oven engineers was working on a large commercial unit, actually they were ALL large commercial units!, he had a blonde moment and forgot to discharge the big HV cap bank which then took a bite out of him. He was very lucky not to have succumbed, it was only the fact we had a very capable first aider on site that saved his life as he had stopped breathing. The whole place held it's collective breath until the word came out he was ok. The paramedics were most impressed with the first aider when they came to take the victim to hospital.

[Tim]

Somehow, my calculations turned out to be completely wrong, and the hole ended up in completely the wrong room!

That's exactly why one usually drills from in to out, as usually it's less vital to get in exactly the right place on the outside, although I have ended up in the "end" of a wall that teed onto one I was drilling. It can be very difficult to judge levels sometimes.

[Martin G7MRV]

About 15 years ago, working in a warden call intercom company, I was sat on the antistatic workbench, whilst I made up a mains lead for a Tunstal Piper control box. I had very carefully bared back and twisted the earth, neutral and live wires, and let the cable drop to the bench whilst I got the control unit ready. Loud bang and everything goes black. Silence. I thought to myself, calmly, "well, thats me dead then". After a few moments I could hear raucous laughing, and thought "oh, Ive killed Andy as well!", then a spot of bright white light appears in the distance...

The light was Andy opening the shutters to our one and only workshop window.

I'd wired the mains plug on first, and it seems that without thinking, had plugged it in and switched on, before starting to work on the other end of the cable!

Exactly why im not dead i'll never know...

[Peter.N.]

Many of us that started in the trade in the '50s have had many experiences of the above and probably many hundreds or even thousands of shocks, working on live valve TVs this was almost inevitable, I'm pleased to say though that the majority including myself survived them.

One experience of that time that comes to mind is when I was called out to clean the screen of a Pye VT4, you had to slide the chassis partway out, turn the set on its side and remove the bottom panel, you could then slide the screen out. I was carrying this process out on a small table when the chassis fell off, the full weight was taken by the CRT tube base leads followed by a hissing noise and an embarrassing confrontation with the customer - we never cleaned screens in the house after that.

Peter

[hannahs radios]

I was borrowing 2 marine receivers about 30 years ago they were too heavy for me to move into my shed so I set one up in our outhouse connected about 10 foot of wire as an aerial I was sat happily playing when my bare ankle touched a gas pipe the shock made me a bit shaky for a while but I wasn't harmed when I got them set up in my shack I made sure they were earthed properly.

[Martin G7MRV]

Got my first shock from the mains aged 4. Someone else made the daft mistake and wired a two pin extension plug on a table lamp with the pins on the live side! I crawled under the dressing table, and still have the hideous pair of scars at the base of my right index and middle fingers.

[Malcolm G6ANZ]

I bought a Decca CTV25, console model, for £10.00. This wasn't the mistake. The mistake was taking it upstairs to my bedroom To give a fraction more room for manouvering I had taken the back off, leaving the tube base exposed. My self and my friend were carefully inching it round the when there was a slight jerk and a hissing sound. Replacement tube time. This was my introduction to colour television. EW tube, set up focus, convergance, et al. The set finally gave a very good picture and was reliable.

Malcolm

[Peter.N.]

Yes, it was a work of art setting up those early colour sets.

Peter

[Malcolm G6ANZ]

It was indeed, especially as I didn't have a cross hatch generator and had to do most of the setup with off air pictures. I will also confess that I only used it on 625 lines. The thought of changing standards was scary, as I had 'stolen' certain' convergancs pots from the 405 side to make the 625 work.
Malcolm

[Philips210]

Back in the early 1980's I had just finished a repair on our 26" Pye hybrid TV. The Antex soldering iron was in a proper Antex stand sitting on top of the TV, a bad place to leave it in hindsight.
I'd unplugged the iron and lifted the stand by the spring. I couldn't believe what happened next. The spring had unscrewed itself from the heavy bakellite base. The base just so happened to be over the tube base board and clocked the base board. Funnily enough, I don't remember hearing the usual hiss but the tube was finished. I forked out for a replacement regunned tube which saved the day but not my pocket!

Lesson learned, don't pick up the stand by the spring. After that nasty experience, I decided not to put any heavy items on top of a TV while working on it.

Regards
Symon.

[SiriusHardware]

Originally Posted by Martin G7MRV

About 15 years ago, working in a warden call intercom company, I was sat on the antistatic workbench, whilst I made up a mains lead for a Tunstal Piper control box..

A familiar name - I worked for a company which primarily made and serviced Warden Call equipment - we serviced Tunstall equipment as well, though I did not work for Tunstall. I witnessed a mistake by one of our installers who was busy putting a wired system into a row of terraced flats with a somewhat uneven roof ridge line. His task was to run a 20-pair 'spine' cable through all the loft spaces, placing junction boxes in every 6th loft or so to which the individual 4-pair cables from each dwelling would be brought. We (the service engineers who would be looking after the finished site) called to have a word with the installer and we were talking to him in the street when an old lady came out of one of the houses demanding to know when something would be done 'about this wire'. We were led, mystified, into her top floor bedroom to be greeted by the sight of a wall with a six-inch circle of plaster blasted off it, with a 10mm hole in the centre and about 30ft of 20-pair tumbling through the hole and lying in a heap on her floor. The installer had drilled through from the next door loft space not realising that the loft he was drilling through from was about 6ft lower than the one he thought he was drilling into.

The same (unlucky) installer was talking to me in a loft space in a row of pre-war council bungalows in which the lofts were really one continuous space, with each loft separated only by a triangular brick dividing wall. He leaned on one of these and in true agonisingly slow silent-movie style, he and the entire dividing wall slowy fell over backwards and disappeared through the ceiling of the next-door bungalow in a choking haze of white dust. Amazingly, he wasn't killed or even badly hurt - nor was the tenant, who happened to be in another room at the time.

[Philips210]

When I was about ten I thought I'd see how quickly the heating element on our Belling electric fire came on by putting my fingers through the guard and resting on the element. Switching the bar on with the rocker switch proved how quick my hand came off the element, not by how hot it was but the terrible shock that I received. It felt like my arm had been whacked by a sledge hammer. Needless to say, I didn't do that again.
I was lucky to have got away with that as we had no RCCBs in our house back in 1976!

Symon.

[Bazil2112]

When I was a 17 year old apprentice back in the mid seventies I decided to test a neon bulb by poking a screwdriver in the earth socket to open up the live and neutral shutters then took hold of the bare wire between my thumbs and index fingers and poked them into the mains socket, i don't know which hurt the most the burns on my thumbs and fingers or the slap across the head i received from one of the senior engineers.

[bill knox]

My first job after leaving school was at Decca in Brixton Road London, I was always looking for scrap units and eventually found in a bin an EHT Mullard psu (these give out 25KV on load), I was given permission to take it home and got it running, my mother called out that tea was ready so I leant over the unit to unplug it, I am not sure how far away from the end of the EHT lead but it arced over onto my arm and it threw me backwards and straight through the doors of my wardrobe and smashed them to pieces.

Another time still at Decca I was in the final test department setting up B&W televisions, we were meant to move the trolleys (with 8 TVs 17" CRTs but no cabinets yet) along its length to get the wheels moving, this time as I pulled the trolley forwards it tipped over smashing 8 CRTs and damaging the chassis's.
miraculously I did not get cut by glass at all but they were picking glass up for days from the assembly line about 25yds away.
It took ages before the ribbing stopped.

[Peter.N.]

The most expensive mistake I have made (so far) was in delivering a new 14" TV, I think it was a GEC, I looked in the boot of my Vauxhall Cresta, there seemed to be plenty of room so I slammed it shut, there was a loud crunch and opening it again revealed a TV with a large hole in the top courtesy of of one of the hinges, I returned sheepishly to the shop and we ordered a new cabinet.

Peter