Need a service manual for a DVR

[steve_qix]

I am in fairly serious need of a service manual (or at least the schematic - particularly of the power supply) for a Panasonic DMR-E85H digital video recorder.  The local access TV studio has two of them, and both have crapped out - within about a month of each other!

These are great units for automation because the command structure is logical and programs can be directly addressed by a number.  No "arrow keys" are needed.  We've had these in service for a number of years, and they really have been working quite well.

I have looked on line and so far, I can only find the service manual for the EC version (European Community), and that uses quite a different power supply.  The problems both do appear to be the power supplies, and they are complex enough that a schematic will really be necessary.  I've made some voltage measurements of the usual things, and everything's good at least up to the switcher - was hoping for a bad diode or something easy    I get "some" output, but not enough - and I am also unsure of what voltages the supply actually needs to produce.

Any ideas where I might find a service manual or schematic?

There isn't anything out there that I can buy new that can replace it with respect to the PRICE and functionality.  The Magnavox hard disc DVR is close, but it is very much not controllable by absolute, computer generated commands.  Everything is "relative" to what the unit is doing or what program is selected, etc. etc (in other words, lots of arrow key navigation - it ignores "numbers" when you are selecting an already-recorded program).  Of course, Leightronix makes $6000 and up units that will work great, but the Panasonic DVRs were less than $250 each - quite a difference.

[W1AEX]

It's a great unit. I have one installed downstairs and it has run daily without any issues. At one time Panasonic had an FTP site where you could grab firmware, owners manuals, and a few utilities for the E-85H, but I don't recall seeing a service manual. Whatever I have is on a hard drive that is installed on a system that I haven't powered up for several years. If that system will start up, I'll look to see what I might have grabbed from there. The Afterdawn and Doom9 video forums may have stuff archived for that machine as well. It the hard drive failed, which is the most common failure, any 120G IDE drive will work. In fact, guys who stuffed bigger drives in there found those would work too, but the E85H would only format it as 120G.

http://forums.afterdawn.com/

http://forum.doom9.org/

[W3GMS]

Steve,
Did you try and contact Panasonic directly?  Not sure if that would help but it may be worth a call.  I don't know how old the unit is, but maybe you could find a used on on the Web to take measurement against. 
Good Luck,
Joe, W3GMS   

[Pete, WA2CWA]

Easy request:
http://www.servicemanuals.net/ServiceManual/PANASONIC/dmr+e85/pos1/results.aspx

[W1AEX]

I have looked on line and so far, I can only find the service manual for the EC version (European Community), and that uses quite a different power supply.  The problems both do appear to be the power supplies, and they are complex enough that a schematic will really be necessary.  I've made some voltage measurements of the usual things, and everything's good at least up to the switcher - was hoping for a bad diode or something easy    I get "some" output, but not enough - and I am also unsure of what voltages the supply actually needs to produce.

Nice find Pete! There appear to be several anecdotal repair sites for the E85H series. The link below discusses repairing the power supply to one unit:

http://www.paul-ashton.com/pandmrrepair.html

[Pete, WA2CWA]

Nice find Pete! There appear to be several anecdotal repair sites for the E85H series. The link below discusses repairing the power supply to one unit:

http://www.paul-ashton.com/pandmrrepair.html

It was the first item on the list when I did a Google search on Panasonic DMR-E85H service manual

[steve_qix]

I have looked on line and so far, I can only find the service manual for the EC version (European Community), and that uses quite a different power supply.  The problems both do appear to be the power supplies, and they are complex enough that a schematic will really be necessary.  I've made some voltage measurements of the usual things, and everything's good at least up to the switcher - was hoping for a bad diode or something easy    I get "some" output, but not enough - and I am also unsure of what voltages the supply actually needs to produce.

Nice find Pete! There appear to be several anecdotal repair sites for the E85H series. The link below discusses repairing the power supply to one unit:

http://www.paul-ashton.com/pandmrrepair.html

Hi Rob,

Yeah, that looks like the European version - my power supply board looks NOTHING like that one.  There are complete manuals (for free, that is  ) for the European version.  But, they are not of much help because the board I have is so very different.

And Pete, thanks for the link.  I did find a couple of paid copies, but so far no free ones.

It is DEFINITELY the power supply in both of my units.  Seems to be the weak link, for sure!

[Pete, WA2CWA]

And Pete, thanks for the link.  I did find a couple of paid copies, but so far no free ones.

It is DEFINITELY the power supply in both of my units.  Seems to be the weak link, for sure!

Of course, in your initial post, you made no reference to "I want it free". 

[KB3DKS]

Steve,
Change out all the electrolytic capacitors. Biggest problem with the switchers.
Bill

[KA3EKH]

Back when I use to do useful work I repaired many Panasonic VTR/DVR decks, mostly commercial or broadcast but not consumer stuff that much. Panasonic is known for undersize voltage regulators or week switching supplies. Did you try the shotgun approach? Change out the hot side filter cap and the switching FET? Know most people want to diagnose the problems but after checking for shorted diodes and DC shorts, from what I recall never happened I use to just change the filters and FET and that fixed 90 % of the switching supply problems and saved lots of time. Panasonic is a good company but up until a few years ago they use the cheapest electrolytic they can get. On many of the older DVC PRO decks we have they all need most of the surface mount capacitors in the video systems changed out after around three years but most of the stuff we bought in the last five years has been better. Maybe it's time for you access channel to buy a new Synergy or Tiltrack system? Analog is dead after all, today everything is SDI.

[WB2CAU]

Steve,
Change out all the electrolytic capacitors. Biggest problem with the switchers.
Bill

While I agree it probably is a defective cap, I'm not a fan of shotgun repairs in general.  Buy an ESR meter (capacitor analyzer) and find the defective capacitor and replace it.  An ESR meter is a necessary tool for the workbench especially when working on modern electronics.

http://en.wikipedia.org/wiki/ESR_meter

[steve_qix]

Well, thanks for all of the very useful replies!  I finally found a partial schematic with the P/S.  There are a LOT of electrolytic capacitors on that board, and I didn't want to just change them all out 

Anyway, there are 4 capacitors on the P/S board that deal with most of the switcher current, and I changed all of them in each of the units.  Both are now working perfectly.  The caps must have developed a high internal resistance, as they did all have reasonable capacitance (as measured on an L/C bridge), and not a lot of leakage resistance.  But, I can't test the ESR directly, which was obviously the problem.

Thanks again!  I'm really glad it was something relatively easy to fix.

Regards,

Steve

[flintstone mop]

Glad you found the trouble Steve........
We would get continuous failures of switching PS's and the same caps all the time. The ones that get hit with the switching pulses.
I don't know if it is heat build up or what design flaw is constantly failing.
Fred

[kb3ouk]

maybe the caps aren't quite capable of handling the pulses?