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Electronics => Repair => Topic started by: warf135 on July 05, 2015, 07:24:18 pm

Title: Motorola 24A Diode Replacement
Post by: warf135 on July 05, 2015, 07:24:18 pm

Hello, I'm repairing a radio that uses an SMD Motorola diode for reverse polarity protection on its power line.
The diode is marked: 24A and from what I can tell, is either: 1.5SMC24AT3 or: P6SMB24AT3 I need to find a suitable replacement for this diode.

Here is a pic of the blown diode:
(http://www.normsweb.com/ext/24A.png)

I'm pretty sure that -being used only for reverse polarity protection- its not important to get an exact match... Any Ideas?

Thanks in advance!

Title: Re: Motorola 24A Diode Replacement
Post by: T3sl4co1l on July 05, 2015, 07:29:36 pm

That's a TVS, not just reverse protection.

Probably, anything SMB/SMC of the same specs would do; SMCJ24A is quite common.  (Make sure it is not the -CA version, which is bidirectional and won't provide reverse polarity protection!)

Do measure the package to verify which one it is (SMB is smaller than SMC).

Tim

Title: Re: Motorola 24A Diode Replacement
Post by: warf135 on July 05, 2015, 07:56:58 pm

Thanks for your quick reply!

Service manual for radio states that it is there for reverse polarity protection no mention of TVS :-//  (and sadly no parts list in the service manual i have) I will try to measure the diode soon.

Cheers!

Title: Re: Motorola 24A Diode Replacement
Post by: warf135 on July 10, 2015, 08:34:22 pm

Hello, apologize for delay I have been unwell...  Original diode is about 7mm x 5mm.

Title: Re: Motorola 24A Diode Replacement
Post by: T3sl4co1l on July 10, 2015, 09:08:28 pm

7-8mm body / overall, should be SMC then.

Title: Re: Motorola 24A Diode Replacement
Post by: warf135 on July 10, 2015, 09:50:08 pm

Thanks, SMCJ24A ordered!