Tascam 238 mods?

christian.marcelli

Active Member
Joined
Nov 8, 2014
Messages
29
Karma
4
Gear owned
Tascam 48
Modding gear has gotten quite popular, but I've never seen mods for the Tascam 238. Did Tascam design the perfect machine? Or perhaps the machine gets the max performance possible given the tape size limitations? I'm not sure I've even seen a DIY power supply recap. Is anybody doing anything interesting with these?
 
I repair them and get them going as they should be and there is not much more to do.
Power supply recaps are done all the time at my shop just not on these yet. The older 122 is getting a recap all the time automatically.
 
Thanks for the reply. If you don't mind, how many years do power supply caps generally last? Does it change if the gear was used vs. sat in a closet? Do you know of anyone who services the MTS-1000 Midiizer?
 
Capacitors come in various grades and they all eventually dry out. There is a value that they call MTBF and also one they call shelf life. The Mean Time Before Failure is of course a average that comes from data they have had or accelerated tests they have done. Most all of these 30-40 year old machines are both past the Shelf life and the MTBF and so are on borrowed time.
I change the power supply caps and with those that are 50% larger in value because the decks were built to minimal cost standards and that the part in the deck including other capacitors may be leaking and thus drawing more power. The 1000uFd to 1500uFd cap is usually a good choice as it does not stress the diodes too much yet it has a better reserve for when solenoid kick in and other power draw instances. Mostly start up of solenoids is when most power is taken.
Capacitors do not just short, open but they can also decrease very much in size and so only provide 1/2 or 1/3 their rates value. Also decks that are left sitting for a long time does not exercise the capacitors and thus allow them to short or decay more quickly- this is why buying a deck and storing it for 20-30 years is a waste of an asset and money and you could do much better on the Forex market than tape deck investment. Rubber parts decay and become liquid with some belts over time too.

As to the MTS-1000 maybe Russ at NJFS could help. We in Chicago never did much work with them. Another thing is even when working with esoteric type of devices in electronics and even never having the service manual, I have in my Radio days fixed items just by checking the power supplies as this seems to be the weakest link in most all devices. This means depending on what your unit is doing it might be again some Electrolytic capacitors in the power section or those sections after that with large caps.
Where to find Russ an ex-Teac Manager of the service facility is-
New Jersey Factory Service, Inc.
16 Chestnut Avenue Suite 103 B
Emerson,New Jersey 07630
201-967-0060
Mon- Wed 8-4 Thurs 8-2 Closed Fri Sat/Sun by appt.
www.njfactoryservice.com
Analog/Digital Audio Repair
 

New posts

New threads

Members online