It was a good time to get an education.I was a UYK-* repairman too.
It was a good time to get an education.I was a UYK-* repairman too.
Yeah, but 95% of them are counterfeit!Now I buy Arduino Nano 3 modules with USB connectivity from China for less than $3ea post free, with maybe 1 million transistors in them!
I sure bench pressed a lot of R390s into rack cabinets in the day! I got so I could do it single-handed.I was a UYK-* repairman too.
https://en.wikipedia.org/wiki/High_Frequency_Active_Auroral_Research_ProgramTubes had their place, in their time just like core memory did. We still have a few for HV regulation in machines making transistors today.
http://forum.allaboutcircuits.com/threads/tube-creep.113198/
I thought the multi-emitter input of TTL was just a simulation of the diodes used in DTL.. No transistor action actually.With a real world bipolar transistor you actually can swap the C and E and it will still work as a transistor, albeit with a much reduced gain of about one.
The input stage of evert TTL gate works in this mannor, so there are real applications for this.
Actual transistor action is actually evident, but strangely enough it is forward action when the input is low.I thought the multi-emitter input of TTL was just a simulation of the diodes used in DTL.. No transistor action actually.
Source: https://en.wikipedia.org/wiki/Transistor–transistor_logic#Fundamental_TTL_gateWikipedia said:During the transition the input transistor is briefly in its active region; so it draws a large current away from the base of the output transistor and thus quickly discharges its base. This is a critical advantage of TTL over DTL that speeds up the transition over a diode input structure.
you can. the resulting device has very low beta.why can't I swap the emitter and collector in a circuit?
As a point of interest, certain 'power type' or otherwise low beta BJTs (e.g. many 'TO-36 packaged' germanium types) do indeed manifest significant 'polarity dysphoria' - to the extent that they exhibit greater gain in small signal operation in the 'wrong' 'polarity mode' --- Of course such operation is inadvisable (to say the least!)...If an NPN transistor is just a layer of P type material between two N types why can't I swap the emitter and collector in a circuit? I remember doing this with some JFETs, source and drain could be swapped.