PVMs have become increasingly sought after for retro gaming enthusiasts over the years, especially good for RGB gaming. I have a few PVMS in my collection now, with my favorite being the NEC XM29. I came across a locally listed 27 inch Sony monitor, and pictures showed it was a Sony 2730QM. Of course I needed to go and check it out.
I know several retro enthusiasts locally who own 2730QM PVMs themselves. Most of the PVMs have had a hard life , having done thousands of hours of work as studio monitors or presentation equipment. I was expecting the same here when viewing the PVM. To my surprise, the PVM looked near new. The seller explained they had owned the PVM since new, and was used for a little bit of video editing, watching some DVDs and spent time in storage. So, a home use only PVM! Almost unheard of, I had to have it. A quick test showed a working screen. It also came with the matching speakers, Sony cabinet and remote control. Happy days.
After getting home, setting everything up and doing a quick test everything seemed in good order. Fast forward a week, and it was time to give the PVM a good run with my Sega Saturn. The picture was excellent, and I really can’t emphasise that enough. Having seen other ex broadcast PVMs, whilst they have a good picture, they really don’t pop like a set with low hours does. First up I thought I would give Daytona USA a good run. Then, after 10 minutes the screen shut itself down. Oh no. I double checked that it wasn’t the Saturn having issues, but unfortunately it was the PVM. These days there aren’t too many repair shops that will look at PVMs, and those that do probably can’t source many spare parts.
Fortunately for me I have a good and generous friend who is self taught in repairing these PVMs as they have a few 2730QMs themselves. They had come across this issue before, which was caused by a faulty H-STAT unit. These are fully encased in a resin block so they can’t be repaired, only replaced. As you can guess, compatible H-STAT units are really rare to find now. My friend had a spare unit, and had found a couple of others that are now in use but that came after searching worldwide for parts. The good news is he had a spare I could “borrow”. The part number is 1-230-712-21, although you can also use 1-230-712-22 or the best option is 1-230-712-23
Firstly for reference I will go over the symptoms. Turning the PVM on, it had a great picture. After a few minutes, the PVM picture developed a slight wobble. Then after a further 5 minutes the PVM would shut itself down. Time to open the PVM up. There are several screws with a symbol next to them indicating they are the ones to remove when opening the case.
Once the screws are out, the rear part of the case needs a good yank to remove it.
Looking from the rear, the H-STAT unit is the red resin block near the anode cap. this has connections to the flyback, and a couple of coax leads down to a connector on the D panel. Looking down, you can see the connector marked “4”. We need to make some measurements on that. Thankfully we can get to it from the exposed side of the D board.
In the picture below, on the bottom of the green board, to the right of C1585 there are set of 6 grouped pins. They stick out enough to attach a multi-meter probe to them. From left to right, we want to measure the voltage between pins 1 & 3, which are HVR1 & HVR2. The voltage here should be about 4.7VDC. Be careful, as pins 5 & 6 (to the right hand side) run 140V.
See below multi-meter leads attached.
Starting out, things are looking good with 4.76V.
However after 4 minutes, the voltage goes down to 0.16V. Then in another 6 minutes the screen shuts off. This indicates the issue is probably caused by a faulty H-STAT.
To remove the H-STAT unit, after ensuring the tube was discharged, the anode cap was removed. These are a bit different from standard CRT anode cap, as they have a plastic mount with a couple of small metal pins. To remove the anode cap the pins need to be pushed in carefully one at a time while removing the anode cap from the tube.
Once the anode cap is removed, be careful of the spring in the anode cap hole on the tube. The red cable leading to the flyback can be removed by pressing the cable in and turning slightly. The H-STAT cab then be unmounted out by removing the 2 screws you see holding the clear frame to the shielding.
Removing the H-STAT completely will require desoldering the leads from the underside of the unit. By default these wires are twisted onto the eyelet connectors, so will require some effort to twist out while the solder is melted. Be sure to note which wire goes to which connector.
Now unfortunately I misplaced some of my photos of the new H-STAT installation! But basically the new unit was orange rather than red. Apparently the orange units are newer and more reliable than the red ones. When installing the anode cap, again be very careful to bend the wire as minimally and gently as possible. The flyback lead should just push in, and the wire leads will need to be soldered on to the tabs as they were previously.
First of all testing the picture put a grid up from an external source. If the H-STAT needs adjustment this will be obvious. The picture below shows the red overscan area to have a slight wobble in the top right hand corner, and the whole image is slightly off centre.
The horizontal adjustment pot can be accessed via the right hand circuit panel, and is marked clearly. A quick shift with this and the picture was centred. I am not sure exactly how to remove the slight line wobble in the top right hand corner. However it is hardly visible when a game is on screen, so is not worth experimenting to improve it.
If you are having problems with a 2730QM there is a thread over at aussiearcade.com that contains a lot of informative discussion. The thread link is https://www.aussiearcade.com/forum/arcade/arcade-technical-and-repair-questions/monitor-and-chassis-repair-help/83299-the-pvm-2730qm-thread-h-stat-issue-colour-bleed-convergence-and-more and is a very interesting read.
So the good news is now I have a fully working Sony 2730QM PVM!
Now if anybody knows where I can buy a new old stock replacement Sony H-STAT from with any of the following model numbers worldwide please let me know: