Hitachi SDT-400 tape player too fast. - UK Vintage Radio Repair and Restoration Discussion Forum

Spudfunkle · 29th Jul 2020, 10:46 pm

Hi all, new here and my first post.

I’ve very recently purchased a Hitachi SDT-400 and am thrilled with how good it sounds. However, tapes play too fast!

I’m guessing this isn’t an easy fix? Any help and advice appreciated.

Thank you.

Records · 31st Jul 2020, 4:39 pm

Its possible the motor for the cassette deck has a speed control circuit and one of the components has given up, which would account for the speed increase. Also at the age of the system you would be advised to replace the rubber drive belt, if your not comfortable opening up there are folks on here who could help you out or guide you through the process.

SiriusHardware · 31st Jul 2020, 7:07 pm

Could also just be a built up 'tyre' of material on the tape drive spindle?

Spudfunkle · 31st Jul 2020, 8:07 pm

Thank you for those helpful replies. I'm worried about dismantling it in all honesty. Is there a stripdown manual / guide anywhere online? I know that's a slim chance.

Ted Kendall · 1st Aug 2020, 12:05 am

When you say "too fast", do you mean just sharp in pitch or gabbly?

SiriusHardware · 1st Aug 2020, 9:17 am

In play mode the tape is drawn past the head by a rotating metal spindle. A spring loaded rubber roller presses the tape against the rotating spindle. Before you take anything apart just make sure there is not a layer of dirt built up on the metal spindle, as that would increase the diameter of the spindle and make the tape go a little bit faster.

If it's going really fast (out of control / chipmunk style) it may be that the tape is slipping through between the roller and spindle.

Station X · 1st Aug 2020, 10:49 am

Perhaps the tapes being played were recorded on a machine which was running slowly?

29th Jul 2020, 10:46 pm	#1
Spudfunkle Diode Join Date: Jul 2020 Location: Swadlincote, Derbyshire, UK. Posts: 2	Hitachi SDT-400 tape player too fast. Hi all, new here and my first post. I’ve very recently purchased a Hitachi SDT-400 and am thrilled with how good it sounds. However, tapes play too fast! I’m guessing this isn’t an easy fix? Any help and advice appreciated. Thank you.

31st Jul 2020, 4:39 pm	#2
Records Hexode Join Date: Jul 2011 Location: Harwich, Essex, UK. Posts: 429	Re: Hitachi SDT-400 tape player too fast. Its possible the motor for the cassette deck has a speed control circuit and one of the components has given up, which would account for the speed increase. Also at the age of the system you would be advised to replace the rubber drive belt, if your not comfortable opening up there are folks on here who could help you out or guide you through the process.

31st Jul 2020, 7:07 pm	#3
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,575	Re: Hitachi SDT-400 tape player too fast. Could also just be a built up 'tyre' of material on the tape drive spindle?

31st Jul 2020, 8:07 pm	#4
Spudfunkle Diode Join Date: Jul 2020 Location: Swadlincote, Derbyshire, UK. Posts: 2	Re: Hitachi SDT-400 tape player too fast. Thank you for those helpful replies. I'm worried about dismantling it in all honesty. Is there a stripdown manual / guide anywhere online? I know that's a slim chance.

1st Aug 2020, 12:05 am	#5
Ted Kendall Dekatron Join Date: Jul 2008 Location: Kington, Herefordshire, UK. Posts: 3,675	Re: Hitachi SDT-400 tape player too fast. When you say "too fast", do you mean just sharp in pitch or gabbly?

1st Aug 2020, 9:17 am	#6
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,575	Re: Hitachi SDT-400 tape player too fast. In play mode the tape is drawn past the head by a rotating metal spindle. A spring loaded rubber roller presses the tape against the rotating spindle. Before you take anything apart just make sure there is not a layer of dirt built up on the metal spindle, as that would increase the diameter of the spindle and make the tape go a little bit faster. If it's going really fast (out of control / chipmunk style) it may be that the tape is slipping through between the roller and spindle.

1st Aug 2020, 10:49 am	#7
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Hitachi SDT-400 tape player too fast. Perhaps the tapes being played were recorded on a machine which was running slowly? __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.