trottr3 / HD / Jim - thanks for following up. I solved the carriage problem by simply screwing / unscrewing the unit back together again and on the 3rd or 4th attempt it worked. No idea why that worked but I then forgot I'd put out this plea. Jim - I'll possibly need your assistance / wisdom in the future so will bear that email address in mind - and the 'coaxing'! Thanks again.
My much loved and regularly used MZ-RH1 unit has broken. Problem is the carriage has worked loose and will no longer retain discs / close securely. Elastic band option doesn't work! Usual sources not interested in repairing it as you can't get spares these days. Does anyone know anyone out there that does repairs in UK? Thanks in advance.