any tv repair techs ?

[racin-snake]

i am looking for a flyback / lopt tester
i was looking at the main sites and i cannot find a supplier in the uk?
the blue anatek ones are coming from canada but i dont want to order one from canada untill i am sure i cannot source one in the uk ?

does anyone know where i can locate a dick fly one or any flyback tester that i can use in the uk ?

thanks in advance ...

[Mjolinor]

That's a blast from the past

I just used to test them by ringing them, it always works and I never saw a need for anything else.. I am sure that is all a bought tester will do anyway.

[racin-snake]

to be honest i do not know how to "ring " the lopt
any chance of a run down
but to be fair a fly back tester is a great first look when fault finding
more for speed and not having top de solder mainly
any help in the how to would be great if its possible ?
i have an esr meter from anatek but its playing up at the moment
seems to be letting some bad caps through the net
maybe component degradation it is one of the first a mk 1

any other lopt test info would be appreciated though
cheers for your reply ...

[allycoops]

any other lopt test info would be appreciated though
cheers for your reply ...

Testing of Flyback (LOPT) Transformers

Any Good To You

[Mjolinor]

The theory is that when you stick a step input into a coil then that coil will "ring".

That just means that the step input current flow is held back by the creation of a magnetic field in the core of the transformer. As it is a single step and not AC the magnetic field dies quickly and generates a voltage in the coil opposing the exciting voltage. That in turn creates another field in the core in the opposite direction which quickly decays creating another opposing voltage and so on till it dies away through losses.

So if you take a square wave generator and connect it to a scope then you will see a square wave on the scope that is nice and sharp with good corners. If you then connect it to the coil of the LOPT you will see a decaying sine wave at every corner if the coil is OK, if the coil is not OK then it won't "ring" so you will see no change in the shape of the square wave.

Oscilloscopes used to be made with a sync pulse connection on the back specifically for ringing coils so if you have an old one it will probably have the output for you to use. New ones rarely have it now sadly.

Is that enough?

[racin-snake]

i think due to the fact i don't have a scope for electronic devices
but do have a couple of automotive based scopes which would just complicate the process for me i think
i shall just look for a fly back tester
i do not want to complicate the thing with a scope and mainly due to cost
many thanks for your help so far

[Mjolinor]

An oscilloscope would be money better spent, you can do most things with a scope and a meter.

[racin-snake]

i have three oscilloscopes a four channel automotive a 2 channel pico and a two channel hand held
to be honest its more hobby than work (ie paying)
so a cheaper coil ringer would suffice for me as its not a real source of work just a hobby

but thanks for your input
i rarely put a scope on a car let alone the bench but i do have an esr and graphing multimeter and so on
just need a lopt / fly back tester to make it a bit easier if you understand

[tango]

tbh u sound like u are not qualified to do any tv repairs
most times its the line output transister that blows, not seen many lopts fail in the years iv been a tv engineer

[racin-snake]

that would be a correct assumption m8
as i have said previously it is a hobby and as it stands i do not "need" a qualification to do so ?
i do on the other hand have and am qualified as an auto electrical tech is that enough ?
and did not think that accreditation was a compulsory item for asking a question on the forum ?

and its not a case of if or when they blow
its more a case of i can test these if i need to

anyhoo
thanks for your input .... oh and tango i do not want the ring tester for televisions ?
i want it to use on any and all transformers i come across
i dont think i have mentioned repairing a television on this thread ?
think its a case of jumping the gun on this one ?

i posted it this way as tv techs are more likely to have heard and know about this tester
i hope this clears this issue

[kegnkiwi]

Hi mate,

You could always give these guys a try, I used to use them when I was doing the odd tv repair a few years ago. They had an little aladins cave.

http://www.irwinelectronics.co.uk/

[tango]

ok i stand corrected sorry
the link allycoops posted has some u can make yourself
which dont look too bad
or u could try places like above
or cpc etc

[racin-snake]

tried the usual places cpc farnells and rs ect ..no joy seems like its coming from canada after the xmas rush ?
they are pretty rare hence the asking tv techs as these guys might have encountered the thing ?

unless i can get a used one
as i aint too familiar with making pcb's ect to make it myself
hopefully they might give me info on the esr meter too as its a good bit of kit when it works properly

cheers anyway