Very rare high quality clone of genuine Sansui Driver Board F-2507 for Sansui AU-20000 or BA-3000!
This is version of F-2507 with BIAS transistor 2SC984 (genuine NOS Hitachi) included on the board. There is an another version of Driver Board F-2507 for those amplifiers what doesn’t has BIAS transistor on driver board (BIAS transistor is on the power stage of amplifier), so you should know what kind of driver transistor yours Sansui amplifier has because those two type of F-2507 boards are not interchangeable!
That board F-2507 what I am selling here is all new, with all electronic elements new! Most of them are today high quality production, but some of them what are very critical for the correct functioning of the board are NOS (such us that BIAS transistor HITACHI 2SC984 (picture "D"), or those Toshiba 2SA818 & 2SC1628 what are very hard to find today (picture "A")!!
All electrolytic capacitors are made by ELNA or Nichicon (Sansui choice at later production) and series of capacitors only specially designed for audio application (such as Elna Silmic , or Nichicon MUSE ES, KZ series)
The most of resistors (maybe 80%) are high precision metal film resistors made by Vishay Dale (CMF and RN series), both trimmers are multiturn BOURNS...
... ceramic capacitors are NPO, those two blue ones are made by MURATA RPE117COG!
About transistors; those three small signal transistors are genuine NEC (!) 2SA992 - 2SC1845 very low noise directly bought from Japan seller (picture "C")!
Another two small signal transistors are KSA733 – KSC945 made by Fairchild Semiconductor (bought directly from Mouser, USA). Those transistors are direct replacement of transistors 2SA733 – 2SC945!
Transistors TR04 and TR05 are genuine NOS Toshiba 2SA818 and 2SC1628, both “O” hfe rank! You should try to buy them today and you will see how hard is to find them, if you are lucky and find them, you will see the price for them! Predriver transistors are KSC2682 – KSA1142 made by Fairchild Semiconductor.
The both connectors are new Mollex made, with gold-plated contacts.
Driver transistors and black metal heat sink are not included. If you wish to buy a driver transistors too, I can offer you two types of driver transistors; one MJE15031/MJE15030 or 2SA968/2SC2238 for which you will pay separately.
Finally about board… The circuit side is the exact copy of the original circuit side of genuine Sansui F-2507 board, but made on much better material which is much more temperature resistant than genuine Pertinax material from which was made genuine Sansui board.
I am doing Sansui restorations (just only Sansui) more than 10 years, and I tried to make that very important boars as the best I can. So many hours I spent for searching proper elements all over the world, on making documentation for producing that board and finally to assembling it…. So if you already have Sansui AU20000 (or BA3000) with the same type of F-2507 board, but damaged, or with burned elements, or any kind of other problem. This is rare chance to get high quality one.
That board is not plug-and-play, installation must be done by a qualified technician only!!!!
All elements are soldered with solder wire which is lead free.