This is for a Customer of mine, not my personal unit, but honestly, having spare parts is attractive. I would break even on the repair but then again, i would have parts on hand to use for future repairs. So there is a benefit to this madness. 
2SA1494/2SC3858 Replacement
- Thread starter nabeelsayegh
- Start date
Just replace with the DigiKey parts. You will likely need some stuff upstream if the amp blew a channel.
You could also consider Toshiba outputs TTA1943 / TTC5200.. Most of the older JVC amps that were 120WPC used 2SA1215 / 2SC2921 MT-200 outputs. I don't know why they switched to such a heavy duty output. Maybe they were cheaper? The 2SA1215 / 2SC2921 are faster transistors.
Good luck!
You could also consider Toshiba outputs TTA1943 / TTC5200.. Most of the older JVC amps that were 120WPC used 2SA1215 / 2SC2921 MT-200 outputs. I don't know why they switched to such a heavy duty output. Maybe they were cheaper? The 2SA1215 / 2SC2921 are faster transistors.
Good luck!
Ended up having to replace a few small signal transistors, resistors as well as the Super-A chip in the same channel that now has the new power outputs. Luckily, i had another scrap JVC that used the same VC5502-2 Super-A 9pin IC's. Job Done!
The Fuxtor
Addicted Member
Seems crazy that those use such high power outputs? Anyways thanks for the tip on where to find some !
This is how I mounted TTA1943 / TTC5200 in place of MT-200 style transistors:
I made these the same outside size as an MT-200 transitor (I copied the dimensions from a SanKen data sheet.) I wish I would have made the aluminum pieces just a little bit narrower vertically. They slightly interfered with the circuit board so I had to file a very small bevel for clearance. These are .090" thick and could easily have been made from .075" or even .060".
I made these the same outside size as an MT-200 transitor (I copied the dimensions from a SanKen data sheet.) I wish I would have made the aluminum pieces just a little bit narrower vertically. They slightly interfered with the circuit board so I had to file a very small bevel for clearance. These are .090" thick and could easily have been made from .075" or even .060".
K-Amps
New Member
That’s a good fitting solution.This is how I mounted TTA1943 / TTC5200 in place of MT-200 style transistors:
I made these the same outside size as an MT-200 transitor (I copied the dimensions from a SanKen data sheet.) I wish I would have made the aluminum pieces just a little bit narrower vertically. They slightly interfered with the circuit board so I had to file a very small bevel for clearance. These are .090" thick and could easily have been made from .075" or even .060".
What are the rails on this amplifier? 1943/5200’s are robust at lowish rails ie below 50v, but at higher rail amplifiers they are not as good as the MJL1302/3281 or even Sankens own 1294/3263’s. In fact the Sankens beat even the MJL’s at over 80v rails.
If this work’s fine, keep it.
On the JVC RX-950V receiver I used those on, they replaced SanKen 2SA1215 / 2SC2921. The Toshiba transistors have a collector - emitter breakdown voltage of 230V. The SanKens are rated at 160V. The rail voltage is approximately positive 66V and negative -66V.
I have played it pretty loud but only driving 8 Ohm Boston Acoustics A100 speakers and it doesn't even get that warm above the new transistors. All in all, I think they are good replacements for my use and I think in the JVC receiver mentioned in the thread earlier. Sure beats overpaying for new MT-200s and finding out they are counterfeit! I have a few of those here that I purchased before I knew about the counterfeiting.
