madbeanpedals::forum

Projects => How Do I? Beginner's Paradise. => Topic started by: turtle441 on July 17, 2014, 07:24:34 PM

Title: Using Sockets on PCB Boards - silly newbie question
Post by: turtle441 on July 17, 2014, 07:24:34 PM
Hi,
So I've built a few pedals before, but all have been straightforward PCB's where I didn't really need to test multiple parts.  Currently working on finishing up a Rangemaster from one of madbean's PCB's and I had a question.  After realizing (after I'd assembled the 3PR board and populated the main PCB) that I'd accidentally ordered NPN germanium transistors rather than PNP requiringa number of flipped components, I've got everything connected and running, I've figured out the values for R1 and R2 to appropriately bias the transistor, and I briefly tested it with a guitar to prove it indeed makes it  louder. 

Right now, R1 and the transistor are socketed.  In a number of posts on various boards, I've seen it suggested that you leave some components socketed to prevent heat damage during installation.  Obviously, for IC's that's pretty easy, but a number of people have advocated that  for transistors as well.  How the heck to people do that and get the components to stay in place!!??  Admittedly, right now the leads are nice and long to allow easy access to my multimeter alligator clips, but I can't imagine they'd be that much more stable with short legs.  Am I missing something, or are you trading ease of installation for the risk that your transistor might fall out when you mover your pedal board?
Title: Re: Using Sockets on PCB Boards - silly newbie question
Post by: jimilee on July 17, 2014, 08:27:47 PM
The trannies stay in place no problem. The issue comes from adding and removing it. The socket then becomes loose. You can tack solder one leg into the socket if that happens. That happened to me ;ast weekend as a matter of fact. I settled on  set of trannies in my wah, and then replaced the sockets. The other thing is more "rare" trannies, you may want to pull and put into another pedal. As a pedal builder, you'll find you have built way more than you will ever use.  :D
Title: Re: Using Sockets on PCB Boards - silly newbie question
Post by: davent on July 17, 2014, 09:17:49 PM
For something simple like the Rangemaster it's pretty quick and easy to breadboard your transistor, tweak components to your satisfaction then solder your values and transistor in and you're done with it.

That said i still socket the transistors.
dave
Title: Re: Using Sockets on PCB Boards - silly newbie question
Post by: Blues Healer on August 24, 2014, 03:16:30 PM
I've only had a transistor come loose from a socket once. That's after being shipped around the country to several different people.
Anyway, there are a few benefits to sockets, and I always use 'em.

with practice, it's easy to tell when a transistor is well-seated

personally, if I needed additional security, I'd probably use silicone sealant, which holds well enough, but is also fairly easy to remove