ETD51 (-030) darlington transistor TO-220 case

chr...@privacy.net

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Apr 25, 2022, 12:45:40 PM4/25/22

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Hi, can anyone point me in the direction of a data sheet for this device
please? Failing that, even some basic data would be useful!

TIA, Chris

Phil Hobbs

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Apr 26, 2022, 11:26:32 AM4/26/22

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I don't see anything online either. Is this a repair problem, or do you
have a box of those things and want to know what they're good for?

If it's a repair, I suggest posting a link to the schematic and a
description of what the box does, to sci.electronics.repair--there are a
lot more folks over there who can maybe help.

Good luck!

Cheers

Phil Hobbs

chr...@privacy.net

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Apr 26, 2022, 11:55:27 AM4/26/22

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Ok, thanks for the guidance. For the record, a BU941ZT was suggested as
an alternative (its a motorcycle TCI box) - but I am not sure on what
basis. Either way, the latter doesn't work whereas the former did - to
some extent :-/

Chris

Three Jeeps

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Apr 26, 2022, 2:42:46 PM4/26/22

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Is what you posted ETD51 the correct p/n? I don't understand the suffix (-030). All combinations of the p/n string turn up empty (house number?)
My cross ref catalogs the most recent is 2010, provides no crosses either.
What does it do in the ckt?

chr...@privacy.net

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Apr 27, 2022, 7:53:19 AM4/27/22

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On 26/04/2022 19:42, Three Jeeps wrote:
> On Tuesday, April 26, 2022 at 11:55:27 AM UTC-4, chr...@privacy.net wrote:
>> On 26/04/2022 16:26, Phil Hobbs wrote:
>>> Chr...@privacy.net wrote:
>>>> Hi, can anyone point me in the direction of a data sheet for this
>>>> device please? Failing that, even some basic data would be useful!
>>>>

>> Ok, thanks for the guidance. For the record, a BU941ZT was suggested as
>> an alternative (its a motorcycle TCI box) - but I am not sure on what
>> basis. Either way, the latter doesn't work whereas the former did - to
>> some extent :-/
>>

> Is what you posted ETD51 the correct p/n? I don't understand the suffix (-030). All combinations of the p/n string turn up empty (house number?)
> My cross ref catalogs the most recent is 2010, provides no crosses either.
> What does it do in the ckt?

ETD51 I think is the generic type whereas ETD51-030 was from a specific
vendor (I think!). It is used as a driver for the primary of the HT
coil for the spark plug.

I have a datasheet for the BU941ZT which declares it to be an NPN
darlington - I just want to check the ETD51-030 has similar
characteristics and, above all, has the same pinout.

Chris

Gonzo333

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May 12, 2023, 2:46:37 PM5/12/23

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Hi Chris ,in the event that you haven't sorted-it , a Bosch BIP373 should work better than the original , though it does have a thermal cut-out past a certain temp. Also , STD901T will also work as many have been fitted to the first-series TCI-boxes for the 81 yamaha v-twins . They are also superior to the originals . Happy-Trails, Dave NZ

--
For full context, visit https://www.electrondepot.com/components/etd51-030-darlington-transistor-to-220-case-35218-.htm

chr...@privacy.net

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May 13, 2023, 12:00:55 PM5/13/23

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On 12/05/2023 19:45, Gonzo333 wrote:
> Hi Chris ,in the event that you haven't sorted-it , a Bosch BIP373
> should work better than the original , though it does have a thermal
> cut-out past a certain temp. Also , STD901T will also work as many have
> been fitted to the first-series TCI-boxes for the 81 yamaha v-twins .
> They are also superior to the originals . Happy-Trails, Dave NZ
>

Ta for that. I never sorted the TCI box and ended up buying a
replacement 2nd hand one. It didn't fix the original problem which
turned out to be...

...the breather 'wadding' in the bike cap fuel vent had become
non-breathing!
This was eventually, and tortuously, diagnosed by realising there was a
marked difference in float level between 'running' and 'static'

Cheers, though, I would like to get the original box functional again so
I'll give those a look.

Chris