Hi all,
I know very, very little about electronics theory or application (so far). My only prior involvement was in USAF a long time ago. The Air Force sent me to Keesler air plane camp in Biloxi, MS to tech school in 1973, where I forgot what they tried to tell me. (I do remember one good ol' boy instructor telling me that basic transistor circuits were the same as basic tube circuits, "only different.")
That said, I just got myself a Hakko 936 soldering station from Parts Connexion and I am committed to learning enough about this stuff to (i) offload the transformer from my Technics DD 'table so I don't get hum when I can afford to buy that Zu DL-103, (ii) modestly upgrade the turntable's PSU while I'm at it, and then later (iii) offload and upgrade the crossover on my Maggie MMG's (the latter is a post for another forum on another day). Building kits or stuff from scratch comes much later.
I've been looking at threads on Vinyl Engine and Audio Circle relating to Technics SL-1200/1210 PSU mods, and based on some of those posts bought a Linear Technology LT317A 3-pin positive regulator to replace the stock 21v regulator, along with a couple of 1% resistors for the voltage divider (100 and 1.5k ohms), a 10uf 50v cap for the input pin, and a 2200uf 50v cap on the output. Reading a little on this site, however, I get the sense that the big filter capacitor on the output could pose a danger to the regulator if the regulator leads are shorted (?) and the output filter cap discharges across the regulator (?). Also, I've read that the size and impedence (ESR?) of the caps can significantly affect noise on the 21v rail. The +21v supply powers the DD motor circuitry, and I'd like that to be pretty clean.
Please (i) explain the danger (if any) from having a relatively large capacitor on the output of the regulator a la Mr. Rogers Neighborhood, (ii) suggest whether such danger(s) can be mitigated at a reasonable cost, and (iii) further advise generally on component choices/changes (i.e., please tell me if I'm doing this bass-ackwards) and the effect(s) that those choices have on the operation of the regulator circuit.
Thank you for your time and for sharing!
Best regards,
Mike
I know very, very little about electronics theory or application (so far). My only prior involvement was in USAF a long time ago. The Air Force sent me to Keesler air plane camp in Biloxi, MS to tech school in 1973, where I forgot what they tried to tell me. (I do remember one good ol' boy instructor telling me that basic transistor circuits were the same as basic tube circuits, "only different.")
That said, I just got myself a Hakko 936 soldering station from Parts Connexion and I am committed to learning enough about this stuff to (i) offload the transformer from my Technics DD 'table so I don't get hum when I can afford to buy that Zu DL-103, (ii) modestly upgrade the turntable's PSU while I'm at it, and then later (iii) offload and upgrade the crossover on my Maggie MMG's (the latter is a post for another forum on another day). Building kits or stuff from scratch comes much later.
I've been looking at threads on Vinyl Engine and Audio Circle relating to Technics SL-1200/1210 PSU mods, and based on some of those posts bought a Linear Technology LT317A 3-pin positive regulator to replace the stock 21v regulator, along with a couple of 1% resistors for the voltage divider (100 and 1.5k ohms), a 10uf 50v cap for the input pin, and a 2200uf 50v cap on the output. Reading a little on this site, however, I get the sense that the big filter capacitor on the output could pose a danger to the regulator if the regulator leads are shorted (?) and the output filter cap discharges across the regulator (?). Also, I've read that the size and impedence (ESR?) of the caps can significantly affect noise on the 21v rail. The +21v supply powers the DD motor circuitry, and I'd like that to be pretty clean.
Please (i) explain the danger (if any) from having a relatively large capacitor on the output of the regulator a la Mr. Rogers Neighborhood, (ii) suggest whether such danger(s) can be mitigated at a reasonable cost, and (iii) further advise generally on component choices/changes (i.e., please tell me if I'm doing this bass-ackwards) and the effect(s) that those choices have on the operation of the regulator circuit.
Thank you for your time and for sharing!
Best regards,
Mike