Pansat 9200 HD Heatsink Modifications
                                                                                               Extended 03/15/2010
                                                                            Extended 01/30/2012
                                                                            Extended 10/08/2016
              SKEW/POLARITY BOARD WEBSITE Extended 10/29/2016
The MPEG II and the MPEG 4 chips on the Pansat 9200 HD STB run hot and the
provided heat sinks are attached with a gob of glue that is very thick.  This glue acts
as an insulator such that the chips are considerably hotter than the sinks.  I removed
the heat sinks and the glue on them and replaced it with Silicone heat sink compound.

This compound is not a glue and the heat sinks must be retained by another means.
For the larger MPEG II sink a beam structure was created using existing motherboard
holes and a phospher bronze sheet to constantly apply pressure.  The alignment was
maintained by the aluminum beam as seen below in the pics.

For the MPEG 4 chip, which was much smaller, two small dots of superglue were
placed at two diagonal corners of the chip for retension.

The first six pictures below are of the MPEG II chip and its heatsink.  The next three
are of the MPEG 4 chip and its heatsink. 

The last 2 pictures show the arrangement used to retain the MPEG II heatsink.

To date this along with a small fan on the top of the case has reduced freezing of the
Pansat 9200 HD by about 20 times.  Initial trials with the fan alone were virtually
ineffective.  Fan speed is set so that it is not audible with a small variac.

To separate the heat sink from the chip I used an Exacto knife (thin flat end blade)
and a small hammer with some very sharp light taps.  Yeah, it can be nervous time in
doing such.  I believe I cleaned the glue off with lacquer thinner.

This change certainly kills the warranty but it is worth it to make it usable.  It has been
in operation for a year or two this way.  It certainly is still a quirky piece of hardware
in other ways but at least under normal usage it is stable.  I believe any DVB-S2 upgrade
board will still fit. (Wrong - a better design follows for the Pansat DVB-S2 Plus to fit).

The tools to part the heatsinks are in the last picture.  A single hit with the hammer
should part the heat sink.  Confirm location of the blade each hit.

Clicking on the below pics provides a 4 times enlargement of such:
Glue on MPEG II Decoder
Glue on MPEG II Decoder
Glue on MPEG II Decoder
Glue on Heat Sink
Glue on MPEG II Heatsink
Clean Chip
Mpeg 4 heatsink glue
MPEG4 chip glue
Clean MPEG 4 chip
MPEG II retainer
Retainer close up

The following pictures are of a second Pansat 9200 HD which I obtained on Ebay.
The Exacto blade (only) was used with the tack hammer to crack off the heat sinks.

The scorch on this MPEG-2 Decoder glue is clearly evident.

The last picture shows an improved design of the clamping hardware where both
the MPEG-2 and MPEG-4 decoder heat sinks are clamped.  Two 1.5" #4-40 bolts
and one 2" #6-32 bolt were used to secure the three legged clamp.  Brass tubing was
resistance soldered to the ends of a 3/4"x7.94"x.092" bar and to one end of a 6.25"
length bar soldered to the longer one.

Existing board holes were again used and the Pansat DVB-S2 Plus Kit does fit ok.

Burned glue
Blade Placement
Blade wi Hammer
New clamp

A third approach to attaching the heatsink is by using a tiny spot of superglue on each
corner between the chip and the heatsink.  Of course, the insulative thick glob of glue
used in the original manufacturing process is replaced by a very thin layer of Silicone
heat sink compound, essentially only present where the heatsink does not acturally
contact the chip.  This provides the best possible conductivity between the two.   This
not only provides good cooling but is clean and simple.

A tiny fan can then be mounted on the heatsink.  Using a 12v fan with a 7 to 9volt DC
supply eliminates any audio noise.  This is done by using six to nine power diodes in
series from the positive source to the fan.  As in the below picture these are covered
with some 1/8" shrink tubing.  If the 9200HD does not have the S2 card installed then
half the socket it normally uses on the power supply board can be used as the 12v

Heat sinking

One More Time on the Pansat 9200HD Heating Problem

One more iteration was applied to end the heating problem of the Pansat 9200HD, not to mention the failure of four (4) can capacitors in its power supply.  The latter capacitors can be easily identified by their rounded tops and in my case are identified in the following picture and sketch.  Three of these are 2200uf 16v can caps and the third a 3300uf 6.3v can cap.  I salvaged some from failed pc motherboards.

PowerSupply Caps

The problem with earlier attempts to limit the heating of the processor was that the area on the chip which needed to be in contact with the heatsink was from .001" to .003" below the surrounding epoxy encasement and ended up having a layer of  heat sink compound filling that void.  Metal to metal contact is the best possible means of transmitting the heat away from the processor.

To remedy this problem the bottom of the stock heat sink was milled to a depth of .003" so the center portion would contact the metal part of the processor as can be viewed in the following picture:

Modified heat sink

Next it was solidly clamped to the pc board processor (with a very thin layer of heat sink compound) as in this next picture with a small fan installed:


To power the fan a header was installed on the power supply board and the regulated 12vdc was supplied through 6 power diodes (dropping the voltage to about 9v) to insure its noise level was not audible.  The result was that the processor heat sink was observed to run at about 20-22° above room temperature.  In contrast, the transformer on the power supply board was about 85° above room temperature and the can capacitor closest to the transformer (which failed) ran at about 55° above room temperature.

While I recognize that few FTA fans have access to a milling machine or a resistance soldering unit this serves as a reference as to one effort necessary to remedy this manufactured shortcoming.   The Pansat 9200HD otherwise works very well and it does not appear that the many overheating occurances, which this unit was exposed to, has permanently damaged the processor.  Evidence of overheating shows up simply in the processor's slowing down to a crawl in exercising commands.

It should be noted that an alternative to the brass clamping of the heat sink is to apply a spot of super glue to the corners of the processor chip.  I did this on another unit as noted above but I do not know how permanent this solution is for the main processor though it has been effective for the MPEG-4 chip on this unit.