Sony KV-M1421U . component level fault finding on this old CRT TV set.

Remember the days where spare parts and service manuals were all available, the golden years, now sadly a long gone thing of the past, this set will outlast any modern fla tscreen TV !
Michael Dranfield.
15-6-2024.

[@MichaelSmith-xm7ll]

Michael it’s take me back when I was a TV workshop technician and so nice to see your skills of fault finding down to component level, love your videos keep them coming when you can!

[@michaeldranfield7140]

Just uploaded another video .

[@pi6706]

We used to have a 14” Sony Trinitron in our kitchen similar to this back in ‘93 with Teletext and you could either tilt it backwards or forwards. I remember being blown away by its picture quality. We had never seen a picture like it. It was like looking at a postcard. Sony sets weren’t exactly cheap but you definitely got what you paid for.

[@danmyers7827]

There's a special richness to a Sony Trinitron picture. I have seen a 14" Trinitron survive years of exposure to high temperatures (>30°C), high humidity & salinity, frequent bouts of shaking, mains voltage excursions and very high intensity local RF fields! The volume control became a bit scratchy, but the set just soldiered on.🙂

[@michaeldranfield7140]

I actually still have one of the sets you refer to that tilts back and as you say Sony sets of this era had mind blowing pictures, they were very expensive to buy back then but well worth the money in terms of picture quality and longevity.

[@pi6706]

@@michaeldranfield7140 Ours had to go for repair once in 2 years as it was stuck on standby and would not turn on. It apparently just needed a component replacing (the repair man did state that it was a safety feature of the TV so was probably the safety device that you were referring to). It then carried on working for many years.

[@whitesapphire5865]

And someone once told me that a Philips G6 was the most horrendous telly to work on! That was a good bit of logic and diagnostic exercise if ever there was one. Brilliant work there, Micheal.

[@michaeldranfield7140]

Sony sets were never my favourite sets for this reason, quirky circuitry, very expensive parts and not very easy to read circuit diagrams.

[@diecksl]

This is my favourite content. I can watch this for hours. It's like a crime investigation.

[@michaeldranfield7140]

no fun repairing flat panel sets , not like the old CRT .

[@neilbaker3395]

Well done Micheal nice one to watch I always want to find the exact cause most rewarding not always about the money more job satisfaction

[@michaeldranfield7140]

Yes , I could have just left the board out but as you say job satisfaction is much more rewarding .

[@anthonydenn4345]

That was quite an unusual problem, nice job working it out.

[@michaeldranfield7140]

Many thanks for that .

[@0mnis14sh]

Fantastic work. Trying to get my head around this stuff is much less difficult with people such as yourself going through how it all works!

[@michaeldranfield7140]

I use to be better than that many years ago ! doing these videos is like a trip down memory lane for me too , trying to remember all the stuff I use to know .

[@Rollin-Rant]

Nice bit of fault finding Michael, I still have a crt television 👍

[@michaeldranfield7140]

Nothing wrong with having a CRT , I still use them at home with Freeview boxes .

[@walker55able]

well done Micheal really impressive fault finding.

[@michaeldranfield7140]

Thankyou .

[@gpo746]

Well Done Michael, good video , fascinating to find the fault on the teletext board , not what anyone would think of . Really enjoy your videos . Many Thanks

[@michaeldranfield7140]

with hindsight it would have been much simpler to just un plug the text board in the first place but who would have ever imagined that's where the fault was !

[@triodehexode]

This is far better than a mistery who done it crime movie . Thank you.😊

[@michaeldranfield7140]

Never thought I would be doing CRT again but for me its like a trip down memory lane .

[@rosscammisola335]

Very good explanation of how it works initially with Chicken and Egg situation that occurred in so many other old Models needed to know the chassis and model background as always , Thanks for the reminiscing Journey back in time

[@michaeldranfield7140]

more to come, I'm enjoying the trip down memory lane myself .

[@Linkvagen]

Always interesting to see a knowledgeable person, like you, solving problems.

[@michaeldranfield7140]

problem is you cant be knowledgeable any longer as new TVs are board only replacement and there are no schematics .

[@OaklynHall]

Another excellent video - thank you for sharing it with us. Its fascinating to see how you go about diagnosing the problem. I really enjoy your videos and always look out for the new videos that you upload. We had one of that type of Sony TV, it was excellent! Once day it just stopped working if only we had known that it may have been a simple fix to get it working again....

[@michaeldranfield7140]

these sets are well worth saving due to the incredible picture quality, a new video has just been up loaded .

[@johnrudd9550]

Nicely presented…I enjoyed that trip down memory Lane.👍

[@michaeldranfield7140]

Me too, life was so much more fun with component level fault finding , all gone now though .

[@johndunleavy]

Nice one Michael. Most interesting and well explained.

[@michaeldranfield7140]

you can see now why sony was not one of my favourite sets !

[@johndunleavy]

@@michaeldranfield7140 Me neither!

[@BjornV78]

Nice fault finding. At arround 16:00 there is a clue, that something is shorted on that signal on the faulty tv. If you look at the scope pattern of the second tv at 16:00, when you turn off the power, the amplitude of the 0,650 V (on) signal goes very slowly back to the 0,5V (standby signal) like if a capacitor is unloading. On the faulty tv the base signal of 0,5V drops instantly to almost zero before it recovers back slowly to 0,5V. That instant drop is a indicator of something "hard" pulling a signal down, like a shorted component does. Nice video, love the troubleshooting, and also admire your collections of components. Grtz

[@michaeldranfield7140]

Glad you liked it, maybe if I had taken more notice of the waveforms but I hardly ever use a scope these days , no fault finding to component level with flat panel sets , its just board replacement and no schematics available .

[@BjornV78]

@@michaeldranfield7140 , the days that things are made to last decades is gone, these days , you got to get lucky if the device doesn't break right out of warranty period. I have a "dumb" Samsung 32" flatscreen since 2013, made it last year a little bit smarter with a Google Chromecast dongle, to watch KZbin etc...works still fine, but since day 1 i have turned the background LED's down, not only to save them, but i found it too bright like it came out of the box. Think this is the main reason it still works fine.

[@monteceitomoocher]

Good bit of fault finding, and you proved the rule that if it's got more than eight pins it's not faulty, unless it's a painter chip...

[@michaeldranfield7140]

The good old painter chip, another blast from the past , I may even have a spare board knocking around .

[@campbellmorrison8540]

I love "friends" like that very tight with their money but not your time! They are the people that buy one bolt because thats all they needed and then when they need another they use your stock on Sunday afternoon.

[@michaeldranfield7140]

my friend is so tight he will hold his hand out for a Penny if you pay him short.

[@deanagoes2791]

Long ago, when I worked at TCL service, the DTC114 transistor failed and became a common problem in TCL TV standby cases.

[@michaeldranfield7140]

No doubt there would have been a technical bulletin then if this transistor was a common problem .

[@phillipyannone3195]

Excellent bit of diagnostics and very well explained.😊

[@michaeldranfield7140]

Thankyou .

[@wisher21uk]

Brilliant fix Michael very in depth really enjoyed it thanks 😊

[@michaeldranfield7140]

Many thanks for that .

[@sodderbridge]

Almost 20 years ago was my last CRT repairs. I remember replacing lots of Philips A10E CPU's.

[@kevvywevvywoo]

I knew philips were on the slide when I saw the A10E. Those big widescreen crts that came with a free hernia operation

[@michaeldranfield7140]

getting up that was since I did crt too, never thought I would be here doing them again but its like a trip down memory lane , memories of much happier days . I may have a A10E board still knocking about !

[@michaeldranfield7140]

@@kevvywevvywoo For me the slide was the G90 , G110 when Philips started using surface mounted components .

[@sw6188]

I got out of repairing CRT sets around 2002. NZ was being flooded with cheap china CRT sets brought in by the container-load and you could pick one up brand new for less than $200. Given that repair to a TV was usually that or more, people decided to stop getting their sets fixed and to buy a "cheapie".

[@kevvywevvywoo]

@@michaeldranfield7140 ooh yes I remember fixing my first G110 with LOP transistor failure and it had taken out half a dozen SMD bits in the e-w circuit, I think some of the suppliers did a kit in a plastic bag of stuff that had to be changed, but memory is hazy

[@daveodessa]

Great work and a pleasure to watch. Thanks for your video.

[@michaeldranfield7140]

Many thanks for that .

[@Falco45able]

Thanks for your time and effort fella! Stay lucky,stay safe!😉

[@bofor3948]

Nice bit of logical thinking on this one. But, when you found something on the teletext board was affecting the stby voltage, at that point I thought ok, obsolete item BIN IT! No you had to find out what had failed. I wouldn't have had your determination. I admire you for that.

[@michaeldranfield7140]

I have always been like that , in the past I have unwrapped capacitors and transformers to see the failure mechanism for my own curiosity .

[@Ped0772]

Fixed 100's of these in the 90's.

[@michaeldranfield7140]

ICP was the most common fault I saw.

[@richardbrobeck2384]

Yes , good old Sony I sold and did warranty repairs at my shop and almost all my older tv's in my house are Sony !

[@michaeldranfield7140]

never been my favourite due to overcomplicated circuitry and expensive parts but this particular set is well worth saving for its incredible picture quality .

[@darrenmurphy6251]

mad fault that one! the input to teletext board was outputting wow, these types of fault can drive you mad, seemingly defying logic definatelly one you take a break from to collect thoughts impressive skills there! wierd that the jungle chip didnt just have a standby input or a more normal inhibit method like shorting a freerun timing r/c that crt looked quite "normal" was it not trinitron?

[@michaeldranfield7140]

No its a Trinitron, you can see the platinum tie wires if you look closely enough.

[@kevvywevvywoo]

nice tellys, I've just gone into the spare room and dug out my 14in sony, came on straight away, havent used it since flat screens came out! A product of Sony's Welsh factories no doubt

[@michaeldranfield7140]

incredible picture quality on these 90 s portables, well worth saving .

[@8-bitbitsa821]

Awesome ! Never give up 👍🏻

[@michaeldranfield7140]

Many thanks for that , I always try .

[@kevb1816]

Good sets, I had a choice between one of these or a Philips 8833 when I had my Amiga. Went for the TV but getting the RGB to work was a pain, ended up making my own scart lead as the shop bought one didn’t work - think they produced Amiga to Sony scart leads later. When the warranty expired I changed the horizontal shift preset for a pot with proper knob and stuck it out of a hole in the back as the Amiga ideally needed the shift to be adjustable.

[@michaeldranfield7140]

Think there was a Decca set that had RGB input that was made for the Amiga but I may be wrong ?

[@daveg8htfadlibaudio250]

Spot on as always 😀

[@michaeldranfield7140]

Many thanks for that .

[@ralphj4012]

Well discovered. Surprised me that standby is achieved by clamping the horizontal oscillator output of the IC.

[@michaeldranfield7140]

its shorted to ground through a resistor which may not have been to clear in the video but yes I have seen that done in a few sets in years gone by .

[@sw6188]

Some manufacturers have done some weird things with their circuitry over the years. I worked on a TV once that had a relay for switching the set into standby. All it did was open the HT rail from the power supply which when running was about 120 volts. When the relay opened, the output of the power supply would rise to about 190 volts (unloaded).

[@ralphj4012]

@@sw6188 Your comment (and Michael's) shows how rapidly my memory is failing (and senility probably increasing). I worked on many TVs around 45 years ago and though I remember crowbar SCRs in power rails, service switches (field collapse) etc., I don't recall seeing signals being clamped, including via resistors, transistors etc. Live and learn (or not, as my case may be).

[@sw6188]

@@ralphj4012 Unless you had need to trace a fault into this territory, you may not have encountered such things. I started repairing TVs in the late 70s as a kid, then did it as a career on and off throughout the 80s, 90s and early 2000s. We're all getting older and as Michael points out, not having worked on CRT sets for some time and you do get rusty. It's like most things - when you do it every day it's fresh in your mind. After 20 years of not doing it, the concepts do get a bit cloudy. When I look at a CRT set these days I have to go back over all my notes in order to remember how to do stuff! I have always written service notes (and still do) because no one can remember everything. Amplifiers I worked on five years ago I have since forgotten, and had I not made notes of the faults and how I resolved them I would probably have to go back and do it all again and waste quite a bit of time.

[@andygozzo72]

nice, i have a KV1442UB that has similar case style, also got 3 of the first trinitron type imported to the uk, kv1320ub mk1, kv1320ub mk2, kv1300 , plus another late model trinitron, cant remember no.!

[@michaeldranfield7140]

To be honest I was never a big fan of sony sets, even worse the hard wired ones but I do have access to loads of them , the guy I repaired this for use to repair TV s in his younger days and he's a bigger hoarder than me and his favourite brand was sony, I must have counted 20 plus early sony sets in just one room he has and I have been steadily buying sets off him , in fact he asked me if I wanted cash for this repair or a TV set of my choice, naturally I took a TV , a video will be coming soon !

[@andygozzo72]

@@michaeldranfield7140 i have some older sony black n white things, 3 TV110UKs, a TV720UK and a small thing about 3 to 4 inch screen, with battery compartment, dual vhf/uhf(uhf tuner dud unfortunately)

[@robtitheridge9708]

I hate to admit it but that set would of defeted me excellent fault finding.

[@michaeldranfield7140]

Many thanks for that .

[@Robjud-u2x]

Nicely nicely 👍

[@michaeldranfield7140]

Thankyou .

[@shodan6401]

It's a shame, looking at that Jungle diagram, I didn't see any RGB outs. No way to mod this nice little unit and add an RGB SCART Mux kit input...

[@michaelwaite6725]

How do you cost a job like that though ? Most people would have given it up as beyond economic repair but well done for going on with it tubes look in good condition for the age 👍

[@Dedubya-]

Tough to charge a realistic rate when the item is essentially scrap, albeit I understand why people want to keep these TVs running. Back in the late 1990's it was hardly cost effective to repair a 14" TV like this so it certainly isn't now.

[@michaeldranfield7140]

its no longer possible to charge a realistic price for anything these days you just have to do whatever you can, my friend is an EX TV repairer from many moons ago but he does nothing with TV s now and he is a bigger hoarder than me , lets just say he has a house full of old vintage TV sets , so when he asked me if I wanted cash or a TV of my choice from his collection you can guess which I chose , a video will be coming soon !

[@michaelwaite6725]

@@michaeldranfield7140 true Michael nice to keep the old sets from the 80s going and our grey matter in working order

[@radio-ged4626]

Mistakes along the way? More like working out the fault through a process of elimination 😀

[@michaeldranfield7140]

true , Im not as good or quick as I use to be though .

[@azshaw123]

Hello Michael, Do you or did you ever carry any new video heads for Beta vcr's, Thank you , Aaron-Greater Manchester

[@michaeldranfield7140]

sadly not , back in those days video head and line transformers were expensive items and were only ordered in specifically for a repair job .

[@Barbarapape]

A rare chance toi do some fault finding to component level rather than just fit a new board. I think most of us would have been scratching our heads with this one. I have found that Sony gear tends to have over complicated circuits that are not easy to repair.

[@michaeldranfield7140]

One of the reasons sony was not a favourite brand of mine , the hard wired sets were even worse .

[@kendom33]

Was it these or another older model that had the line output faults? Nightmare. Great video Michael. Goodness standby !! Thank you

[@michaeldranfield7140]

cant remember with sony , what does stick in my mind is the Hinari CT5 and Fidelity sets with common LOPT failure .

[@Petertronic]

Nice fault finding work. I had the 21" from this range of tv's the KV-X2121U, it was an excellent and reliable set, apart from dry joints on the audio amp chip which was a common fault.

[@michaeldranfield7140]

Hmm , if that set you mention was in a dark gray plastic cabinet with fibre back I have one of them .

[@tonyweavers4292]

Brilliant work Michael. I hope you are going to charge your mate for the repair.

[@michaeldranfield7140]

he asked me if I wanted cash or a TV of my choice from his collection , he's a bigger hoarder than me and has a house full of TV s , I took a vintage TV , video will be coming soon .

[@adamdavies163]

Love the curiosity, the need to find the exact cause. 🙂Hope you're keeping well!

[@michaeldranfield7140]

I have always been like that , I once un wrapped a transformer to see what had gone wrong !

[@mosfettg6857]

Nice job in finding the culprit, It shows a novice like me how complicated the old sets were.👍

[@michaeldranfield7140]

Sony sets were not my favourite for this reason, quirky electronics, pricey parts and not to easy to read circuit diagrams compared to other manufactures .

[@sw6188]

As time went by, CRT sets became more complex with all the additional circuitry like Teletext. Sony always seemed to over-engineer their sets as well, a bit like Philips.

[@sw6188]

@@michaeldranfield7140 I'll second that. Over-engineered electronics and over-inflated prices for their parts. I have tried to avoid Sony stuff for these very reasons.

[@Lightrunner.]

Ohh the good old time😍🥰🥰 and Sony😳...🤣 Good work , nice vid👍👍👍👍

[@michaeldranfield7140]

Many thanks for that .

[@roberthorwat6747]

Superb! Glad you decided to gave the teletext decoder a good going over. Bring back CEEFAX I say😊

[@michaeldranfield7140]

before teletext there was a service that rad down the telephone line to your TV set, I seem to remember it was called Prestel ?

[@pauldavies6037]

Wow that's a good fault why Sony used such a complicated start up /standby circuit God Knows that teletext board was used on the larger Sonys around the same time had dry joints and text decoder chips fail only

[@richardbrobeck2384]

I have like that Sony !

[@michaeldranfield7140]

well worth keeping just for the picture quality .

[@repairitdontreplaceit]

great work michael i love working on sony stuff , great schematics etc

[@michaeldranfield7140]

Not my favourite , there are many other sets with much simpler circuitry and easier to read schematics .

[@leetucker9938]

that was awesome diagnosis , best thing I seen all week

[@michaeldranfield7140]

Many thanks for that .

[@darrenjukes8446]

Brilliant as always

[@michaeldranfield7140]

Many thanks for that .