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-   -   JVC HR-D120MS - Squeaking noise when lacing up (https://www.vintage-radio.net/forum/showthread.php?t=191268)

dj_fivos_sak 18th May 2022 2:17 pm

JVC HR-D120MS - Squeaking noise when lacing up
 
Hello everyone. I recently acquired this VCR (model number in the title) and it's working well except there's this squeaking sound every time the machine finishes the lacing/tape loading cycle. You can hear it in this video:

I haven't done any work at the bottom of the mechanism and I suspect something needs to be lubricated in there. The same noise is produced when returning from forward/reverse search back to play. Any suggestions before taking the machine apart would be appreciated.

PS: The more common UK model that uses this chassis is the Ferguson 3V35. Mine is the multi system JVC version. Other than that they are identical.

Fivos

its ur aerial 18th May 2022 5:43 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
I don't recall ever doing a 3V35, but the 3v22 / 3v30 and such like used to suffer with a squeak from the bearing on the bottom of the capstan motor fly wheel, a quick clean and a tiny squirt of lubricant or what have you, restored operation.

Ken G6HZG.

dj_fivos_sak 18th May 2022 8:03 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Hello Ken. It's not the capstan bearing that's causing my issue. The 3V22/HR-3320EK is a top loader with piano keys so it's a totally different model, and the 3V30/HR-7300EK is a later generation top loader with soft touch keys and its mechanism somewhat resembles that of the 3V35/HR-D120EK.

Fivos

ben 19th May 2022 9:09 am

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
If you're referring to that brief noise at 4 - 5 seconds in to the video, they all did that.

vhs doctor 19th May 2022 7:23 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
During CUE or REVIEW function the sounds remain tbe same?

dj_fivos_sak 19th May 2022 9:59 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Yes Ben. That's what I am referring to, but I am fairly sure it shouldn't make that noise.

vhs doctor, here's a video showing all the functions.
One odd thing I noticed on the MS variant of this machine is that you have to hold the FF/REW buttons down to get it to do picture search, unlike the E/EK/EG/EM variants where you only have to press the buttons once and let your finger go.

Fivos

vhs doctor 20th May 2022 6:32 am

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Hi

I have exact the same problem on my ITT VR3905 the mechanism is the same. The sound was created from the loading motor pulleys and the loading belt. You must clean the pulley surface and use a smaller belt to solve the problem.

dj_fivos_sak 20th May 2022 3:51 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Thanks for your suggestion. I will first try pouring the original belt into boiling water for several minutes. That should shrink it a bit and reduce its diameter by a couple of millimeters.

Fivos

dj_fivos_sak 25th May 2022 4:22 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
1 Attachment(s)
So, I took the machine apart and tried what vhs doctor suggested, but the issue still persisted. Then I came to the conclusion that the squeaking noise is coming from somewhere in the loading ring assembly. The P2 and P3 tape guides are sitting on top of these two plastic rings which turn in opposite directions when the tape in lacing/unlacing, and the noise is created whilst spring-tension is being applied onto the guides to lock them in place in the fully laced position. Do I have to tear the chassis down into bits in order to lubricate this assembly?

dj_fivos_sak 25th May 2022 4:35 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Sorry for the multiple posts. Just wanted to include a video with the machine apart to help you see (and hear) the issue more clearly.

Fivos

dj_fivos_sak 26th May 2022 6:33 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
4 Attachment(s)
Hello. I finally found the solution, and the fault was indeed inside the loading ring assembly. Here's what I did to fix the problem:
1. Remove the front panel (1 screw and 3 tabs/clips), and remove front loading mechanism and unplug it.
2. Unplug all the connectors connecting the mechanism to the Audio/Servo/Mechacon PCB. They are marked so be sure not to mix them up when reconnecting.
3. Remove the head drum grounding electrode, the RF shield over the video head connector PCB (also unplug the connector for the video heads), the chassis grounding lug with its three grounding wires, and the back-tension lever (don't touch the adjustment screw!). Then, remove the 5 screws securing the chassis/mechanism onto the cabinet.
4. Turn the chassis over and unplug the connector of the head drum motor.

*continued in next post↓↓

dj_fivos_sak 26th May 2022 6:43 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
4 Attachment(s)
*continued from previous post

5. After unplugging the head drum motor connector, turn the chassis over again and remove the 7 screws securing the sub-deck assembly to the main chassis, then remove the sub-deck assy with the heads, guides etc still attached to it.
6. The loading ring assembly will be exposed. You can mark the two rings and chassis to help you align them when putting everything back together, but that's not really necessary.
7. Remove the loading ring assy (3 screws)
8. Clean up the old graphite grease and apply some new lithium grease.

Now it's time to reassemble the machine by reversing the order of disassembly. After doing so, the loading mechanism should run much quiter and smoother, as seen here.

Hope this helps anyone having the same issue with an HR-D110/120/220/225 or 3V35/36/38/39! :)

Fivos

Nickthedentist 26th May 2022 9:41 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Well done and thanks for documenting it so well.

dj_fivos_sak 27th May 2022 2:05 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
Thank you. One thing I forgot to point out is that even if you've marked the position of the loading rings in relation to the chassis, the loading mechanism might still get out of alignment after putting it together. In that event, you'll need to slacken off the loading motor block so that you can move the P2 and P3 guides freely and individually, and once they are aligned/timed correctly, you can then re-fasten the loading motor block with its gears and verify the alignment by turning the loading pulley by hand. The tape guides should reach their V-blocks at exactly the same time, otherwise the mechacon microcomputer will go haywire and run the loading motor for way too long, and that might cause the circuit protector of the loading motor's power rail to blow up.

Regards

Fivos

ben 27th May 2022 3:03 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
That's the first time I've ever heard one of these lace up without that graunchy squeak! You learn something new every day ;)

dj_fivos_sak 27th May 2022 7:31 pm

Re: JVC HR-D120MS - Squeaking noise when lacing up
 
I have an HR-D110EG which is suffering from the same issue. Gonna do that next. I wasn't even around when these machines were popular but that noise immediately caught my attention. :)


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