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Transistor Substitutions

Hello guys I've been collecting this kind of lists to make a nice table, I wonder if it will be useful to create an small webpage/database where you write the part that your looking for and display the recommended sub with a note and disclaimer like ''best used in this or that application'' or something like that.
I could use one of my servers for that matter/
 
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Hello guys I've been collecting this kind of lists to make a nice table, I wonder if it will useful to create an small webpage/database where you write the part that your looking for and display the recommended sub with a note and disclaimer like ''best used in this or that application'' or something like that.
I could use one of my servers for that matter/

I've been compiling a list of substitutes over the years, that I've gleaned from here both by rebuilding my gear and asking for assistance, as well as following other threads about other folks rebuilding their gear and asking for assistance. I would be glad to offer the list for vetting as well as inclusion into a database/webpage effort such as you described.
 
nice!, so seems like a l good idea then?
So far I have a table like this for start, a ''searchable" pdf

I think it is a really good idea to have a web page that allows you to plug in an obsolete transistor and get current suitable substitute........ but my expertise maxes out at creating a simple spreadsheet. :(
 
I think what might be helpful is a table of new replacements with their voltage, current, power ratings, and maybe some suggestions on what their best use is. I could put this together fairly easily.

For me being able to cross reference every transistor isn't as valuable, I just look at the datasheet for the specs, then find a suitable replacement from my list of common new replacements.

I'm sure there could be a list of about two dozen transistors that I'd replace with one part.
 
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nice!, so seems like a l good idea then?
So far I have a table like this for start, a ''searchable" pdf
I think it would be an excellent idea. You could imagine that I started with a different format, but it was hard to maintain that format and bring it to the forum.
Please go for it and I am sure you would be making many ppl happy.
 
I think it would be an excellent idea. You could imagine that I started with a different format, but it was hard to maintain that format and bring it to the forum.
Please go for it and I am sure you would be making many ppl happy.
Don't worry about the format.... The replace tool on excel is magnificent (Jeremy Clakson voice).
The important thing is the data :thumbsup:
 
I'm working on a general guide for selecting replacement transistors without a cross reference. It will include a list of commonly recommended parts and their key specs.
 
I'm working on a general guide for selecting replacement transistors without a cross reference. It will include a list of commonly recommended parts and their key specs.
I have written a draft of this guide, I took the liberty of starting a new thread for it:
http://www.audiokarma.org/forums/in...nsistor-replacements-using-datasheets.757254/
Comments, elaborations, corrections welcome and encouraged.

We can include a cross reference sheet as an addition resources too.
 
Guys, this is awesome!
I am really glad to see the works towards a centralized location.
Hippocrates, your application would be great , I am sure, but it would be even greater if there was a way to integrate it with AK.

Raccoon and dlucy, thank you very much for your thorough explanation on how to choose a replacement, as well as for the suggested replacements you provided. THANK YOU!
 
Can someone explain the difference in the original Marantz part numbers HT313281T and HT313282A which were 2SC1328T and 2SC1328S.T - how does this relate to substitute? Can KSC1845 be used for both?

Thanks for your help.
 
I do not know anything about the marantz. I am assuming the original parts are located in the audio section.
The S and T suffix of the original tranies are their gain classification. For C1328U gain was impressive (over 1000) In your case S = 260-520; T = 360-700. For the C1845F, which is still available, gain is between 300-600. Both are low noise, so you should be fine.
 
I do not know anything about the marantz. I am assuming the original parts are located in the audio section.
The S and T suffix of the original tranies are their gain classification. For C1328U gain was impressive (over 1000) In your case S = 260-520; T = 360-700. For the C1845F, which is still available, gain is between 300-600. Both are low noise, so you should be fine.

Thanks!
 
I have the dilemma of having a few thousand different transistors on hand and finding a sub within my collection is time consuming. I had an idea of potentially writing a winforms (windows) application which would:

1) function to import what transistors i have via single column excel document into the winforms application. Once submitted, have the app loop thru the rows, parse alltransistors.com (emulating a browser) and return scraped results of parameters, save to local db or excel file.
2) textbox to enter in the transistor to be subbed.
3) once a value is entered in textbox, have a routine emulate a browser to parse alltransistors.com and scrape the results and parameters to the application and save in a local database or excel file. Display results in a grid.
4) if returned results show you have one onhand, highlight those transistors in a grid within the app. If not, show possible subs, giving fairchild subs higher priority maybe.
5) perhaps have a list of known good subs collected on AK pre imported into the app, if no matches, proceed to alltransistors parsing routine.
6) an update routine to grab latest excel list of good known subs from the web into the application, maybe a server of an AK member
7) perhaps a reverse lookup method based on selectable transistor parameters to help compare against onhand devices.

This could be made into a webapp eventually. Waste of time or useful? Alltransistors.com reliable enuf for data? Sometimes i find misinformation on that site comparing to manufacturer datasheets.
 
Your dilemma of having "a few thousand" transistors sounds like a blessing and a curse. How do you store all of them? A few thousand is like one a day for the next 6 to 8 years.

I am assuming that you have a file that lists your inventory of TRs. I'd just use other sources to get a list of suitable subs, then plug that into your file to see which ones you have. Alltransistors.com is a good place to start, but I like to check other sources to get some concurrence before I take a leap.

Any kind of a webapp that you could develop would only be as good as the data that could/would be entered. If you leave this open to the public it could be hosed in a matter of hours. The other option is to screen all inputs yourself -- a very time consuming process.

I also think that most hobbyists benefit from the process of researching TR subs. It is one of the few ways that I learn anything.
 
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