Go Back    Forum > Digital Video > Video Hardware Repair

Reply
 
LinkBack Thread Tools
  #1  
04-05-2016, 05:16 AM
MPJVC MPJVC is offline
Free Member
 
Join Date: Apr 2016
Posts: 2
Thanked 0 Times in 0 Posts
Hi all,
I had a customer donate me a Panasonic AG-MD835 medical S-VHS VCR with a low drum hour count of about 30 hours with original head drum intact and has not been switched on for over a decade. It required some re-timing on the mechanism but now it can play tapes. There is minor black streaking/comets on extreme luminance transitions (so far in VHS mode) like small text but not always as it depends on the content. The test tapes are known to be good. Being a portable recorder, SMD electrolytics are everywhere, so that would be some cap-hunting. Anyone have experience with this model?

I know these medical VCRs are rebrands of the industrial broadcast models. Is there a known equivalent in the broadcast field for this VCR and what kind of TBC does this one use? Thanks in advance.
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Ads / Sponsors
 
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
04-05-2016, 07:05 AM
Goldwingfahrer's Avatar
Goldwingfahrer Goldwingfahrer is offline
Remembered
 
Join Date: Aug 2013
Location: Switzerland
Posts: 453
Thanked 84 Times in 74 Posts
The TBC in the AG-MD-835 are not as good as the big Panasonic AG 7650 or 7750th

Capacitors I have no change.
Elko patients here are the last Pana AG 8600 + 8700

Manual cut-side 4 to 15

I have about 5 AG-MD835 with 9 H .......1500 H
but can not speak English.


Attached Files
File Type: pdf AGMD835P.pdf (567.6 KB, 35 downloads)
Reply With Quote
The following users thank Goldwingfahrer for this useful post: lordsmurf (04-25-2016)
  #3  
04-05-2016, 06:26 PM
MPJVC MPJVC is offline
Free Member
 
Join Date: Apr 2016
Posts: 2
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Goldwingfahrer View Post
The TBC in the AG-MD-835 are not as good as the big Panasonic AG 7650 or 7750th
Hi Goldwingfahrer,
Thanks for the info. Do any of your AG-MD835 units have black comets/streaks during playback of tapes recorded on consumer VCRs?

I expected the typical line TBC because the dropouts were compensated line by line. This is probably the last of the industrial VCRs in my area and it was free so better make the most of it. I hope to put up some image captures of it in action by the end of this week. As I don't have the exact service manual for this (I have the AG-MD830 manual which has circuit layout differences), it'll be some guess work for identifying the bad caps.
Reply With Quote
  #4  
04-06-2016, 08:41 AM
msgohan msgohan is offline
Free Member
 
Join Date: Feb 2011
Location: Vancouver, Canada
Posts: 1,323
Thanked 334 Times in 276 Posts
I thought black streaks around luma spikes = bad video head, not electrical issues.
Reply With Quote
  #5  
04-06-2016, 11:06 AM
Goldwingfahrer's Avatar
Goldwingfahrer Goldwingfahrer is offline
Remembered
 
Join Date: Aug 2013
Location: Switzerland
Posts: 453
Thanked 84 Times in 74 Posts
Quote:
Do any of your AG-MD835 units have black comets/streaks during playback of tapes recorded on consumer VCRs?
No

Pana AG MD 835 Line TBC.. No.... = Full Frame TBC
I give the signal from the MD-835 to a Data Video DAC 7 [SDI-out] in the PC = = resultat properly.
I have about 4 Pana AG-MD-835 and about 2 AG-MD 830th
AG-MD-830 do not have full-frame TBC
and no line-TBC.

The Pana AG-MD-830 I have to connect to the Canopus NX.
The Canopus NX has a full-frame TBC.

I have the Pana AG-MD only PAL models


Attached Files
File Type: zip AG MD 830E_SM_PANASONIC [GESICHERT] - PDF-XChange Viewer_2016-04-06_17-36-01.zip (216.5 KB, 12 downloads)
File Type: zip Pana AG MD 830.zip (39.9 KB, 11 downloads)

Last edited by Goldwingfahrer; 04-06-2016 at 11:27 AM.
Reply With Quote
The following users thank Goldwingfahrer for this useful post: lordsmurf (04-25-2016)
  #6  
04-25-2016, 01:30 AM
lordsmurf's Avatar
lordsmurf lordsmurf is online now
Site Staff | Video
 
Join Date: Dec 2002
Posts: 13,510
Thanked 2,449 Times in 2,081 Posts
Honestly, medical VCRs were limited in ability, made for recording and NOT playback, were (ab)used heavily, and were in generally nasty conditions. I would not get anywhere near one, even if free.

- Did my advice help you? Then become a Premium Member and support this site.
- For sale in the marketplace: TBCs, workflows, capture cards, VCRs
Reply With Quote
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
Panasonic NV FS200 powers on, usage, connections? Orientation Video Hardware Repair 13 04-11-2016 03:41 AM
UPS planning/usage: Active PFC UPS? Skylake? VideoTechMan Computers 2 03-27-2016 08:28 AM
Panasonic AG-W1 plays in black and white only? Misterkeeks Video Hardware Repair 6 01-15-2016 03:11 AM
How to limit bandwidth usage in WHM? Brent Web Hosting 0 09-13-2013 06:38 PM
How to use the Disk Space Usage tool in cPanel Brent Web Hosting 0 08-25-2013 08:41 PM

Thread Tools



 
All times are GMT -5. The time now is 09:27 AM