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Help, trying to replace a transistor!

Jordan gunn

Jul 13, 2017
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Jul 13, 2017
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IMG_8014.JPG Hello I'm trying to locate the transistor in my radio I watched a YouTube video where a guy repaired a very similar radio by replacing its transistor and claimed it was a common problem for this model. I have bought a 2n2222 transistor to replace it with but the layout in the video is slightly different than mine and I can't locate the transistor to replace it. Anyone know which one it is?
 

73's de Edd

Aug 21, 2015
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Sir Jordan gunn . . . . .

Need brand and model # of your unit.

Describe your units problem . . . dead? . . .distorted sound . . .very weak sound . . . .picks up few stations.

The one thing that you DO have going for you is the fact . . . . that unit is amongst the last of the pocket transistors and is using silicon transistors in the form of those black topped Fairchild units in your set . . .AND . . . a 2N2222 works/subs for a whole bunch of transistors.

73's de Edd
 

Minder

Apr 24, 2015
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Apr 24, 2015
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It looks like an old one,Hopefully not the germanium transistor kind, usually there is a number on the transistor
With those many times the problem semi can be identified using a can of cold spray/Arctic Air which can bring them back to life momentarily.
This is IF it is a semi problem.
Two or three of them will be RF type transistors.
M.
 

duke37

Jan 9, 2011
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Measure the voltages on the transistors. Silicon transistors will have about 0.6V between base and emitter. The collector will be more positive than either with an npn transistor. Measure voltages relative to 'chassis' which with npn transistors will be connected to the battery negative.
The emitter voltage can indicate if the transistor is passing current.
 

kellys_eye

Jun 25, 2010
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Hold the radio close to another radio operating on the same band.

By varying the tuning of one of them you will hear a 'whistle' (called heterodyning) that will indicate the local oscillator is working correctly.

If you CAN'T get this whistle then the transistor closest to the RED tuning coil will be the dud one.
 

ramussons

Jun 10, 2014
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Jun 10, 2014
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View attachment 35121 Hello I'm trying to locate the transistor in my radio I watched a YouTube video where a guy repaired a very similar radio by replacing its transistor and claimed it was a common problem for this model. I have bought a 2n2222 transistor to replace it with but the layout in the video is slightly different than mine and I can't locate the transistor to replace it. Anyone know which one it is?

How about a link to the original YouTube video? Maybe we can guess which transistor was replaced.
 

73's de Edd

Aug 21, 2015
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Sir . . . . Jordan Gunn . . . . . . . . . . . . . . . ( Not ? ? ? THE . . .famous Jo Jo Gunn ! ? )

( http://www.theworldaccordingtorandy.com/files/Beatles - Get Back.mp3 )

Ya’ know what ? . . .we thinks that maybe that you forgot to give the ALL IMPORTANT Brand and its Model number.

ALSO hook a battery up and put your ear against the speaker. Turn on to see if you hear any initial “ plop “ noise at turn on, from the speaker.

At turn on, run the volume control up and down, rapidly, to see if there is any “ staticy “ noise on its movement, being heard from the speaker ?

Any semblance of reception when you leave the volume at max and tune across the AM band . . .. from end to end ?

System Identifiers:

AM_RAdio_Markup.jpg



73’s de Edd
 
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