i amstill using 1975 kraft transmitter and 1982 futaba gold transmitters with new narrowband recievers because they are non computerized and easy to setup and the kraft 7z transmitter is setup for easy trim adjustment and has great pots on the sticks .i use it for test flying.just keep them maintained and serviced reqularly and you should be ok check with either the radio manufacturer or pete at kraft midwest for service.pribably have to change batteries but that should be done about every 5 years anyway.i sell off my used batteries that are older than 5 years or on used radios i buy as long as they have no dead cells then use that money to buy new packs also eliminates disposal problems.most all transmitters can be gold stickered with a tuning and no other modifications,you may have to buy narrow band recievers to bring the flight packs upto date.you can find used on ebay and rcu.let me know in a private message what the manufacturere is and model numbers of the components and i can help tell you what they are.