From what I've picked up, the germanium transistors do not react well to being soldered (easily killed by heat), so they're socketed most of the time.
My question is, is there any reason as to why most people leave the legs on them really, really long, with insulation on them?
Quote from: alanp on May 09, 2013, 08:19:25 AM
From what I've picked up, the germanium transistors do not react well to being soldered (easily killed by heat), so they're socketed most of the time.
My question is, is there any reason as to why most people leave the legs on them really, really long, with insulation on them?
The insulation is to keep the legs from touching each other.
I leave the legs long so I don't have to put the transistor right on top of the socket. Inconvenient, especially in a 1590A! But sometimes I solder the transistor into the socket (especially black glass, which have really thin leads), and so it's good to have some extra length to avoid damage and be able to get them out later if I need to.
Quote from: alanp on May 09, 2013, 08:19:25 AM
My question is, is there any reason as to why most people leave the legs on them really, really long, with insulation on them?
Because that's what Sola Sound did back in the 60s (& it looks very nice) ;). (Check out the original Tone Benders if you've not)
Ge trans are not as readily killed when soldering as some ppl make out. As long as your soldering skills & technique are good there's no worry, esp if you keep the legs long.
It's good practice/insurance to use a heat sink on the legs, but if your soldering is up to scratch you can get away without one.
The insulation on the legs also strengthens them a bit &, I think, helps prevent sharp bends or kinks when folding the transistor over (sola sound style).
Also, long leads with insulation allow them to be snaked around other tall components (like radial electro caps), which helps in small enclosures.
And then there's the "keeping it stock" vintage factor....germanium transistors keep their value better when the legs are long.
And some of these things ain't cheap!
Sent from my Nexus 7 using Tapatalk HD
'Nother silly question, do pinouts vary at all, or can I just put my Smallbear 'Generic PNP Germanium Tonebender' set straight into the pastyface board?
Pinouts do vary depending on the particular Ge transistor, but any I've ordered from Smallbear have matched the most common pinouts (such as found on the Mangler, Pastyface, etc.).
The Q1 SB supplied looks like a teeny weeny coke can with leads (and no tabs), not like the giganto-germanium Q2 and Q3 that match the silk screen. I think I'd better google pinouts for all three just in case, anyway :-\
The friggin' leads are too small for the sockets, too. This must be karmic payback for the Ring Stinger working first pop with absolutely no issues.
One thing I do on senstivie parts is I do one leg at a time and solder something else or do something else on the build. I figure it can't hurt. Generally I agree 2-3 seconds on a leg and to the next one should be fine but I always have crap all over my desk so I can just reach over and hit something else while I let the legs cool.
And who doesn't like an awesome pair of tranny trousers ;D
Never had an issue soldering a Ge transistor. The thin legged ones can be a bugger in sockets though (rattling around, took me ages to find the intermittent problem in one build and it was transistor rattle). Sheaths are just to stop the legs touching. Leaving them long allows for easy removal if you fancy scavenging them for something else.
Hey alanp,
Your DEFINITELY going to want to check the pinout of the transistors before you start messing around with them in the circuit. I've found inserting ge's the wrong way is more likely to kill them (happens rarely)then soldering them directly (never happened before).
A few options for thin legs; 1) if they are really thin you might be able to bend then in half, and flatten them with twissers / plyers and insert then that way. 2) the best sockets for ge's i've found are the ones on mammoth. They are the TO18 sockets. Pricey, i know. I have been using one in a ge leakage tester for 6 months now. Probably inserted about 500+ transistors of all shapes and sizes and the socket is still grabbing the legs firmly! They also grab thin legs well as well.
Paul
I don't socket transistors of any kind, unless I'm specifically making a testing PCB.
With one notable exception, every circuit I've seen that uses germaniun trannies as a critical part of the sound is simple enough to breadboard first. I'll test out trannies, changes some passives values around to tweak it, and then once I'm happy I'll solder everything to the PCB.
For germanium, i'll leave the leads a little longer so they can be easily removed and repurposed in the future, if need be.
hey guys,
what about this heat sinkers for the trany lags. where can I buy it? or can I make it with a heat shrink tube? :P
cheers
Alligator clip on the leg, works as a heat "sink" as you solder, dissipates the heat, Matt.
The question is pretty good and most of the posts are informative as well. I am going to ask a question about silicon and germanium products. I was told by an Electrical Engineer that one of the reason for earlier German and Japanese made products to last longer than today's Chinese-made electronics was: Germans and Japanese used Germanium as the semi-conductor and now China-made electronics uses silicon as the semi-conductor. How true is this statement? It got me a little interested as both elements lie in the same column and both are semi-conductors. I have seen parts made up of silicon rather than Germanium-made parts and I had always thought that use of silicon was due to its availability and I also presumed that silicon and germanium had similar quality. I would greatly appreciate if anybody can shed some light over this curiosity.
pcb assembly (https://www.7pcb.com/PCB-Assembly-Service.php)
Quote from: kimsin on July 22, 2013, 10:01:32 PM
The question is pretty good and most of the posts are informative as well. I am going to ask a question about silicon and germanium products. I was told by an Electrical Engineer that one of the reason for earlier German and Japanese made products to last longer than today's Chinese-made electronics was: Germans and Japanese used Germanium as the semi-conductor and now China-made electronics uses silicon as the semi-conductor. How true is this statement? It got me a little interested as both elements lie in the same column and both are semi-conductors. I have seen parts made up of silicon rather than Germanium-made parts and I had always thought that use of silicon was due to its availability and I also presumed that silicon and germanium had similar quality. I would greatly appreciate if anybody can shed some light over this curiosity.
hey, im just starting building pedals and dealing with germanium trannies. I think that there is a lot of voodoo about this topic, they few scientific facts I know: :P
Germanium has 32 electrons and the configuration distribution per layers is 2-8-18-4 The last for are the free valence electrons.
Silicon has also 4 free valence electrons in its last layer, but less total atoms: 2-8-4
this difference makes Germanium a better conductor at certain temperatures than silicon. the "dopping" of Germanium crystal structure will be more pronounced than Silicon (it has much more electrons that can move inside the crystal, leving empty spaces in the crystalline structure.
now try to transfer this to differences in Fuzz sound..ehehhe, I don't know....
cheers