KLH21 - Looking for a transistor sub

E

exray

Jan 1, 1970
0
Hi,
I'm looking for the elusive audio driver transistor in the KLH 21-
series radios. It is house marked as KLH5351. Early 70s.

Any help would be appreciated. The normal sources are turning up dry.

TIA,
Bill
 
W

William Sommerwerck

Jan 1, 1970
0
Do you have access to the NTE catalog? (I think it's available on line.) If
you have the patience, you might be able to find a useable substitute by
studying the descriptions, looking for voltage/current specs and uses.
 
T

Tim Schwartz

Jan 1, 1970
0
exray said:
Hi,
I'm looking for the elusive audio driver transistor in the KLH 21-
series radios. It is house marked as KLH5351. Early 70s.

Any help would be appreciated. The normal sources are turning up dry.

TIA,
Bill
Bill,

What case is it in, a TO-220 (plastic case with a metal tab) which
means your radio is likely to be a 21-II, or a TO-1, a small metal
cylinder?(as used in the original, white grill clothed radios) In this
case I'm assuming the output transistors, not the drivers. If I'm wrong
about that and you do mean a driver transistor, please let us know the
case style and (if known) polarity.

Regards,
Tim Schwartz
Bristol Electronics
 
E

exray

Jan 1, 1970
0
Hi Tim,
Its the driver transistor, Q5 in the schematic. PNP, TO-92 style
plastic case.

Tnx,
Bill
 
M

Michael A. Terrell

Jan 1, 1970
0
exray said:
Hi,
I'm looking for the elusive audio driver transistor in the KLH 21-
series radios. It is house marked as KLH5351. Early 70s.

Any help would be appreciated. The normal sources are turning up dry.


It's not listed in the 1985 ECG index (ECG212M). There are a few KLH
parts listed but not that one.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
M

msg

Jan 1, 1970
0
Michael said:
It's not listed in the 1985 ECG index (ECG212M). There are a few KLH
parts listed but not that one.
FWIW, 1996 ECG has a KLH5353 = ECG197:
PNP -Si, AF Pwr Output
Vcbo = 90 V
Vceo = 80 V
Vebo = 5 V
Ic = 7 A
Pd = 50 W
f sub t = 0.8 MHz min
h sub FE = 20 min
case: TO-220

Michael
 
E

exray

Jan 1, 1970
0
FWIW, 1996 ECG has a KLH5353 = ECG197:

Yep, thats one of the output transistors for the same model. Its even
in my old 1973 SK book :) The other half of that complimentary pair
is the 5352.
 
T

Tim Schwartz

Jan 1, 1970
0
exray said:
Hi,
I'm looking for the elusive audio driver transistor in the KLH 21-
series radios. It is house marked as KLH5351. Early 70s.

Any help would be appreciated. The normal sources are turning up dry.

TIA,
Bill


Bill,

Your radio is a KLH-21-II

I worked on 2 of these last year, one of mine and a friends. I've just
opened mine, and its NOT the one that I replaced the driver transistor
on. However, it is a Motorola PNP bi-polar transistor in a TO-92
package. No reason not to use another Motorola device, like the 2N5400:

PNP
To-92
120V(CEO)
600 ma
625mW
40-180 beta
same pin out
really inexpensive and readily available.


If you feel really uncomfortable about this substitute, I can ask my
friend to take his apart and see what we used it it.

Regards,
Tim Schwartz
Bristol Electronics
 
E

exray

Jan 1, 1970
0
Your radio is a KLH-21-II

I worked on 2 of these last year, one of mine and a friends. I've just
opened mine, and its NOT the one that I replaced the driver transistor
on. However, it is a Motorola PNP bi-polar transistor in a TO-92
package. No reason not to use another Motorola device, like the 2N5400:

If you feel really uncomfortable about this substitute, I can ask my
friend to take his apart and see what we used it it.

Regards,
Tim Schwartz
Bristol Electronics

Actually mine is the 21 AM/FM but apparently this Q5 is the same
according to the older SAMS info vs what is in the radio. If it
wouldn't be too much trouble I really would appreciate some
confirmation on what actually worked. I've got to do this via mail
order and would like to get it right the first time. :)

Thanks,
Bill
 
W

whit3rd

Jan 1, 1970
0
Yep, thats one of the output transistors for the same model.

That's useful info. KLH was a US company, either RCA or Motorola
would be likely transistor suppliers. ECG 196/197 crossrefs
to the 2N6292 and 2N6107. So with those as the final, the
driver would likely be 80V, 250 mA rated... like MPS6717 (NPN)
and MPS6729 (PNP)
 
E

exray

Jan 1, 1970
0
Thanks folks, I think one of the s.e.r fans is bailing me out of my
dilemma via email. Thanks to all who offered suggestions and advice.

-Bill
 
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