Marshall Amp GR100RCD Transistor Help

[pmonti244]

I need to replace two transistors in my Marshall GR100RCD Amp, they are 2SA1386-P and 2SC3519-P. I searched on the web and was only able to find a datasheet for the 2SA1386-P which called for negative values for VCBO, VCEO and VEBO. All the other datasheets I found were for 2SA1386-2SA1386A and 2SC3519/2SC3519A which calls for positive VCBO, VCEO and VEBO values.



This is where I get confused can anyone tell me what the –P means.



In addition if anyone can tell me where I can get replacement transistors and what part number I should be looking for. I would greatly appreciate it.


Thanks

 

[nigelwright7557]

-p probably means plastic cased.

Look up the other numbers and see if they look like your transistors, if they do they will likely work ok.

You need to put your location on so we know how to help you better finding components.

 

[Enzo]

The NPN vs PNP-ness of a transistor is indicated by the 2SC or 2SA starting the part number.

Some transistor makers spec PNP types with negative voltages. Others just list all voltages as positive - or at least no polarity indicated. Nothing cosmic there, you can;t install an NPN with the negative at the collector and positive at the emitter and expect it to work. SO don;t read more into it than is needed. They are all the same part.

And I'd agree that P probably means plastic. Are your old ones of the fully insulated tab variety? Similar to a TO3P?

Wherever you find those type numbers, the parts will be right.


MCM has both for a little over $3 each.

 

[fjc]

The spec of sanken 2SC3519 is there on the web. P means HFE range 70-140. They are other two HFE ranges O (HFE 50-100), Y (100-180). P does not mean plastic. I am searching and looking forward it to replace 50W MJE 15032/ 15033 as the driver in my power amp. It seems is a overkill. But I have HFE matched pairs (A1386/C3519) to replace not so matched 15032/15033. Any suggestion?

 

[Ian Finch]

Agreed, P is not marked on examples as part of the type number. It's clearly below, alongside the date code. Ebay sellers obviously don't understand marking conventions. Sanken Datasheets support that.

@fjc
Yes, post or link to to your design in your OP thread so a selection can be made. Otherwise, it's just guessing and a waste of time.

 

[fjc]

Thanks for the suggestion, it is not my design, basically it is a push pull design,with symmetrical design on the positive and negative rail. So matching is very much required to avoid DC out put. I will try to give a image of the circuit here.

 

[fjc]

Thanks for the suggestion, it is not my design, basically it is a push pull design,with symmetrical design on the positive and negative rail. So matching is very much required to avoid DC out put. I will try to give a image of the circuit here.

I do like to express the schematic diagram, and upload it to the photobucket as a picture-jpg file but fail to show it here properly . Anyone like to show the steps to download the picture here from photobucket web??

 

[JonSnell Electronic]

I have been and still am a Marshall Amplification repair agent and have never seen a GR100RCD. Marshall do not show it as one of theirs! There are no G anything listed.
Any chance of a diagramme please?

 

[fjc]

Yes, I just get help to show the diagram, and it works now.

 

[fjc]

Sorry, the correct diagram is shown below.

 

[fjc]

I am searching and looking forward it to replace 50W MJE 15032/ 15033 as the driver in my power amp. It seems like an overkill. But I have HFE matched pairs (A1386/C3519) to replace not so matched 15032/15033. Any suggestion? The Q14/Q15 is the oreginal (MJE15032/033). The pre-driver pair Q12/Q13 (2SC3421/2SA1358) is also thought to be replaced by 2SC5171/2SA1930 fpr better sonic performance.