UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players

Notices

Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

Closed Thread
 
Thread Tools
Old 8th Apr 2021, 11:03 am   #1
pentoad
Hexode
 
Join Date: Feb 2011
Location: Newcastle upon Tyne, Tyne and Wear, UK.
Posts: 280
Default Lamp limiter bulb question.

Is it recommended to use one to test a solid state tape recorder which has not been used for a while - just in case?
It has a 160ma, fuse so would a 40watt bulb be appropriate?
pentoad is offline  
Old 8th Apr 2021, 12:07 pm   #2
SteveCG
Nonode
 
Join Date: Jun 2009
Location: Herefordshire, UK.
Posts: 2,495
Default Re: Lamp limiter bulb question.

My answer would be yes - provided the equipment is old enough not to have a switched mode power supply (SMPS). SMPSs can have odd properties when the input mains voltage is well below the nominal working voltage. I would have thought that a 40 Watt bulb would be alright, Just bear in mind that motor operation (eg play, rewind etc) will draw more current...
SteveCG is offline  
Old 8th Apr 2021, 2:31 pm   #3
ortek_service
Octode
 
ortek_service's Avatar
 
Join Date: May 2018
Location: Northampton, Northamptonshire, UK.
Posts: 1,395
Default Re: Lamp limiter bulb question.

You could probably use a much lower wattage bulb to start with, as sold-state tape recorders probably only draw a few Watts - hence the low 160mA fuse.

60W / 100W bulbs were often used for more power-hungry devices, and often used to diagnose TV SMPSU faults, to stop it all going bang at switch-on and taking the 3.15A fuse out.

The main smoothing capacitor in most tape recorders, will be quite small & low voltage, and probably find that reforming with these isn't generally necessary as much less susceptible to breakdown and leakage as HV ones in vintage equipment. Probably more likely for capcitor to dry-up and be open circuit, plus small transformer in these will limit current from being too massive

But no real harm in having a bit extra extra surge-limiting to start with, rather than the fairly-low 160mA fuse blowing (Might still do, with a 40W bulb if there was a severe overload).
ortek_service is online now  
Old 9th Apr 2021, 8:08 pm   #4
pentoad
Hexode
 
Join Date: Feb 2011
Location: Newcastle upon Tyne, Tyne and Wear, UK.
Posts: 280
Default Re: Lamp limiter bulb question.

Thank you
I tried the 40watt bulb limiter, I also tested the filter caps for esr. Luckily switch on was fine. Mind you it didn't work at first but i fixed the fault, there was a bodged repair hiding in wait!
pentoad is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 1:06 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.