'Kingdom for a transistor info'!!!

can you determine the characteristics of a remaining transistor, and then replace the set with new comparable

Lucky you, according to my ancient archives, your 18458H (which is a house number) crosses to an ECG386 / SK9262. I would presume that NTE still carries it under NTE386. It could be possible to find a standard 2N number by using a parameter search (using the NTE data) at someplace like ON Semiconductor and save some bucks. This appears to be an high voltage audio power output transistor.

Good luck

If you need any more help, just ask.

Found the info in an old TCE/SK replacement guide (circa1986)

Here is a link to a source:http://www.moyerelectronics.com/index-16.html

This number crosses to a sk9262 and an NTE 386.

Specs are also available from this link.

cost around $20 each.

Good luck...not many discrete component techs around anymore, were an endangerd breed,mate!

---------------------SSB--------------------------------------

Exactly the same happened to me with a so old drive for a electrics motors in Paceco transtainer crane with G.E. drives (transistors type,80's).Those numbers are just for that special application and you won't get any cross reference, sorry about that.May be picking up your telephone's company...you could get coupple in somewhere.Think better in replace the whole.Once came people from Siemens with theirs plc's and changed it all.

In the future you won't get it any more even if you solve it for now.-

Hi,

why not try to measure, estimate, look into the DC voltage to get the maximum DC voltage to be switched.

Be careful if motor braking is included, this will add back emf-voltage. We shot TO3 housings by this and had holes of diameter 8mm in the metallic covers of these transistors.

Then try to establish the maximum current that should be drawn. There will be a fuse to look at or an overcurrent circuit.

Then think about safety margins (I decided to have 1.5 in voltage and 2.5 in current). Transistor price is not a problem but replacement will take some time.

Then look at second breakdown: if too high a voltage is combined with too high a current is existing at the same moment (both within allowable limits) then you may blow your new transistor in microseconds.

Be sure that cooling is adequate.

Good luck!

RHABE

thanks to all that responded, especially to Wiz & SSB, that came up with a 'horse', pardon me, a transistor.

Luckily me I made a right guess and ordered yesterday MJ13333 which is a NTE386.

Let you know when it's up & running (fingers crossed), wouldn't believe how service-unfriendly this drive is, no regards for a serviceman whatsoever.

cheers,

Kaz

p.s.. Yes SSB we are dying breed, but those old clunckers we be around here for some time and nobody but us would be able fix them

Kaz:

Since we're kind of working in the dark, not knowing circuit parameters and the 18458H's real specs, working from a cross reference can be problematic. While it is a bit of a pain, since these are house numbered parts, you might be smart and try to measure some of the important parameters of this drive circuit. DC bus voltage, transistor current, any flyback pulses, etc. and then try to match up a JEDEC match to be sure.

After looking at the MJ13333 (the MJ13335 has the same ratings as the NTE386), you are probably covered. If these transistors work without problem for a month or two, I would strongly suggest getting a supply of them for repairs. Unfortunately, the discrete transistor list has been contracting severely since the big down turn in the electronics industry back in the '80s.

Motorola was, by far, the world's largest discrete transistor manufacturer, its spin offs have cut their transistor lines massively. Anyone who has older equipment that wants or needs to keep it working are advised to look for transistors now and lay in a supply of them as things are only going to get worse. May metal cases are being discontinued and even some plastic types are shrinking in quantity.

NTE is now the only 'replacement' source, having bought up the competitors and they are often way over the top on pricing (like the NTE386 is way more than the MJ13335). NTE is a place of last resort, with the exception of second tier semi sources which also charge an arm and a leg.

Spending some money on now on standard transistors will save you a lot in the future (or even now).

A word of caution here, I have found the NTE (and others) crosses to be incorrect at times, beware and double check the specs of the replacement transistor or you may be in for trouble.

Good luck with your repairs, Kaz.

Hi There,

Is it possible that you can send me digital photos of your drive:

Photo of board inside,

complete photograph of drive as it is

photo of name plate

any other photo you feel may be useful in identifying the drive.

my email : mail.automation@gmail.com

Regards,

Mahesh Thakur

www.nitinbearings.in

Indl Atmn Dvsn

Chennai

India

dear friend

i have also same problem if you get any solution

pls send me mail shrikant.varpe@gmail.com

shrikant