I have a box of the above each neatly packaged into pairs but cannot find any reliable info
they are branded motorola, made in Mexico and dated 7551 (51st week of
1975).
They appear to be germanium transistors with the strangest case i've ever seen!
I'm trying to decide if i dump them, sell them on e-bay or keep them.
Does anyone know of any uses for them or for that matter want them!
Best Regards,
Darren McInnes
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P
Phil Allison
"Darren McInnes"
** Hexagonal pack - right ???
** E-bay will just love 'em.
** My data book says they are Germanium, PNP with current and voltage specs similar to a MJ2955.
............... Phil
A
Alan Rutlidge
find
7551
ever
Or could be a TO-36 ? Round case (1.25" dia, 0.5" high), with 2 leads in a triangular formation with insulated index pin and threaded bolt with a solder eyelet through the centre of the underside of the package? (RCA may have used a different packaging to Motorola).
specs
My RCA Manual says - obsolete Germanium PNP VCB 100V VBE 80V Ic 15A Pt 150W HFE min 25
Cheers, Alan
T
Trevor Wilson
**Similar specs as a 2N174. Case is a TO-36. This was common with high power Ge trannys.
PNP VCB 100 VEB 80 IE 15 Amps IB 4 Amps Thermal R (Junction to case) 0.5oC/W Common Emitter cut-off frequency 10kHz (!!!!!)
Pretty potent device for a Germanium tranny.
Trevor Wilson
www.rageaudio.com.au
M
Michael A. Terrell
These would be great for the mid '60s to early '70s car radios that used a DS501, 2N173 or 2N174 transistors. I have the three page Motorola data sheet in the 1970 Motorola Semiconductor data book, but it is very hard to scan because the paper is so thin you get print through. I'm looking for some black construction paper to reduce the effect. If I can find some I'll scan it for you.
BTW, the T)36 case was often referred to as a "Doorknob"
Former professional electron wrangler.
Michael A. Terrell
Central Florida
J
John Crighton
Hello Michael, this fellow can join the end of the queue! :-) Remember the HP411A schematic scan you were going to do for me. I bet you forgot!
Happens to me a lot lately, I walk into a room and wonder "What did I come in here for?"
Regards, John Crighton Sydney
M
Michael A. Terrell
I didn't forget, it just takes time to piece multiple page schematics back together. Here is part of the manual:
formatting link
formatting link
I still have to do a lot of cleanup to the rest of the manual.
Former professional electron wrangler.
Michael A. Terrell
Central Florida
D
Darren McInnes
Thanks everyone i can't guess as to the package so here's a link
formatting link
apologies for the quality of the images and the web site I only put it up to share the photo!
and again thanks to everyone for the help.
Best Regards,
Darren McInnes
SNIP
D
Darren McInnes
Thank you very much Michael it would be greatly appreciated but don't go out of your way I have too many projects on already and doubt I could do anything with them soon!
They have been sitting in a box at my new house for a year, before that 15 years in Alphington, Vic. and then in my father's house since 79!
Darren McInnes
J
John Crighton
Hello Michael, the quality of those diagrams are fine. I can read them. Thanks for that. I am going to enjoy poking around in this old millivoltmeter. I never imagined in a voltmeter there would be an electric motor spining a disk with holes in it that allowed light to travel along a plastic tube to shine on to light dependant resistors. Now I can see a 100KHz oscillator there too! I wonder what that does.
With the circuit from you, Michael, I can get this old meter partly working. Half the probe is missing, the bit with the diodes in it. When I find that part or a replacement probe, there is a chap down in Adelade who has some probe accessories for sale, then it will all come together. Excellent! You know, this is news groups working at their best. I am enjoying this.
This is my type of electronics. Knobs, switches, motor, meter, valves, transistors and all in the one box too. I love it! Thanks again Mike. :-)
Regards, John Crighton Sydney
K
KLR
Saw these in a old piece of ex-army surplus equipment back in the early 80's. A pair of them were used to drive a centre tapped 12v primary of a transformer to use it as an inverter.
As I recall judging from the application and current being drawn at the time, I would agree with phils and alan's comments as being similar specs to a 2955 type device.
D
Darren McInnes
They actually come in pairs in sealed plastic bags possibly matched?
I'm tempted to actually do something with them now!
Darren McInnes
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