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post #1 of 614 Old 01-07-2003, 05:26 AM - Thread Starter
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I thought of doing this back in December. But decided that the month of January would probably be better, that way we can start 2003 out by giving our prized Marquees a good maintenance work over.

I think we should keep this open to anyone, and feel free to ask any question, or contribute any experience that you may have. There's always something new to learn about this projector.

I think the Marquee is very near its tenth birthday. It's the only commercial grade CRT projector (that I know of) that has maintained it's basic design for that period of time, and in its basic design, it continued to challenge and outperform a many CRT competitor, and did gain great status in the very demanding commercial and industrial arena. But over its ten years of being one of the best, there have been some minor changes made by the manufacturer, likewise there has also been some field experiences that has made it a much better performer as the years went on. So maybe it's time we share what we know, so that all who has one can possible make it better.

And much thanks to Mark Haflich, who has loaned me one of his 9500's so that I could sharpen my tools. It's been fun. I'm now able to successfully repair most of the boards in a Marquee. There's only been two boards that I've not been able to repair, that is the processor board and the HVPS. The processor board rarely fails, so it's been hard to get my hands on a defective one, and the HVPS is on the bench as I type. And it's only a matter of time, and I'll place it among the rest of the repairable modules. If that coil in the potted material does not fail, I'll have that power supply licked. I know exactly what's inside, and I'm prepared to remanufacture a certain component if it's a problem. I'm confident that I'll be able to resurrect these power supplies.

I myself won't get into tweaks, but let's be open for discussion on them. I'm not doing this to promote business for myself, I'm willing to share a lot of what I know (not all), and most of what I'll share you can do yourself, or have a competent technician do it for you.

To start, we'll cover the neck boards. This is a very important module for performance in this projector. It's the weakest link for performance on a Marquee, there has been several changes over the years to this board. And this was the biggest negative on the early 8000's - We'll look at and discuss how to improve the bandwidth and correct that high frequency roll-off problem (soft image/smearing) that plague the early Marquees.

We'll also discuss the blanking problem (blanking out on bright scenes) and the fix.

And I'll try to remember to post the power supply's cleaning procedure, very important for ventilation.

That's enough for now, I'll get back to this later today

It's all about the performance... Got Marquee!

 

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post #2 of 614 Old 01-07-2003, 05:32 AM
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Hi Mike Parker

The short answer is YES. I will check this thread on every forum
visit for your follow ups. Thanks for sharing.

DH
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post #3 of 614 Old 01-07-2003, 06:32 AM
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Yes as well, please post all details of Marquee maintainance and improvement, they are an easy pj to pull apart, it would be nice to be able to do something with it when its apart.
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post #4 of 614 Old 01-07-2003, 06:47 AM
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Thanks, Mike. Sounds like a great idea.

Marvin Holland
Flower Mound, Texas
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post #5 of 614 Old 01-07-2003, 06:52 AM
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Hi Mike

I'm waiting with a hot soldering iron in my hand

When you say you wont get into tweaks, do that mean you don't do them or are not willing to share them? I remember you once said that you have some component updates, but you where not willing to share them, "for the moment". I was hoping the moment had come

Kind regards, Claus
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post #6 of 614 Old 01-07-2003, 07:09 AM
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Mike,

This is just a great idea, and considering you are not gaining anything monitarily, I applaude your commitment to the projector.

I'm sure everyone will appreciate what you're doing. You're very kind.

Ted

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post #7 of 614 Old 01-07-2003, 12:18 PM
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Mike,

that's very generous of you !
I hope in the near future to be able to profit from your vast experience and knowledge of the Marquee

Thanks

Regards,
Pedro
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post #8 of 614 Old 01-07-2003, 02:41 PM
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Mike I applaud your generosity... this is the type of thing that makes forums like this utterly addictive.

I just bought a Marquee 8500 and I know it could benefit from some good lovin )

I PM'd you last night with a particular concern but I will keep my eyes on this thread and hope that an FAQ evolves from it with contributions from all the Electrohome Wizards that frequent the forum.

Stephan
Vancouver, B.C.
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post #9 of 614 Old 01-07-2003, 04:02 PM
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Me too! I will watch and read with great anticipation. You mentioned some areas where my projector could use help. Soft image and so on.

I am a new member and the search function has let me down every time, so I would love to see all information whether old or new.

Thanks so much!
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post #10 of 614 Old 01-07-2003, 05:38 PM
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Need I really say anything

Thanks a million...Good luck...Let us know... Whichever is appropriate this time! jmwj03 at hotmail dot com
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post #11 of 614 Old 01-07-2003, 06:21 PM
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Mike, It would be great to have a list of capacitors to replace, with better specs or just similar specs for older marquees, if this makes sense PQ-wise.
Rob
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post #12 of 614 Old 01-07-2003, 06:46 PM - Thread Starter
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We're not going to use the boards part numbers for this. So you'll have to visually inspect your boards for the following:

1, look for the numbers on IC 'U2' (near the mini RCA jack). On that IC you should see one of the following numbers: 'CLC409, CLC449, H1100.

2, Check transistors Q12 and Q19, see if they are round metal (TO-5) devices, or small square (SOIC) devices.

3, Check the opposite end of the card for four soldered on 'blue' capacitors.

4, Inspect the solder contacts of resistors R13 and R28, for burn at the point of soldering on the PC boards surface.

5, Inspect coils L8 and L9 for any indication of heat damage.

--------------------

(1) If IC 'U2' is a CLC409 it should be replaced with IC CLC449. Also if there's a H1100, it could also have a softening effect on the image, because it was later replaced with CLC449 (and some H1100's were also on the later boards 8500, 9500's).

(2) If transistors Q12 and Q19 are metal (TO-5) you have an early version card, and this board would more likely have the CLC409 or H1100 chip.

(3) The 'blue' caps are on the early version boards only, as they were a part of the upgrade for the brightness blanking problem that was also on the early version boards. Don't try this fix yourself, this is the protect circuit, and much care should be taking to prevent tube damage if the procedure is not done properly (that I won't provide). Also, much care must be taking when servicing this area of the board. This board SHOULD NOT be used for random modding, it has special interferance tweaks that were necessary for FCC compliance.

(4) If resistors R13 and R28 show burn marks at the solder contacts, replace capacitors C1 and C26. That burn is an indication of high hour use, and C1 and C26 would most likely test leaking. The value is 22mfd @ 100 vdc. You can replace with the same value, but use 105c (high temp) 160 Vdc caps.

(5) Coils L8 and L9 are 100 uh, and would more likely show indication of heat damage if the same is seen on resistors R13 and R28.

For further maintenance of this board, make sure that the solder contacts on resistors R13 and R28 are resoldered. Also use denatured alcohol and a regular tooth brush and saturate the board with the alcohol, and then lightly brush the component side of the board with the brush. This cleaning will remove any oxidation and other crap from the board.

Let the board dry for at least one half hour before using. the alcohol should dry in a few minutes, but it may still be wet in some crevaces.

And make sure to not consume the alcohol !

It's all about the performance... Got Marquee!

 

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post #13 of 614 Old 01-07-2003, 07:15 PM
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Count me in too!!!!

This is going to be another really great thread.
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post #14 of 614 Old 01-08-2003, 01:51 AM
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i will be following and seeing what i can do

thanks

Wendy
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post #15 of 614 Old 01-08-2003, 07:46 AM
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Hello Mike

I have completed the electrolytic capacitor replacement, Resoldered
the resistors and put a CLC449 chip in place of the CLC409 on all 3
neck boards. I still have 3 CLC449 chips for a future job on the VIM.
Now a friend is wanting to do these mods on his M8500 too. So I
need to order at least 6 more CLC449s. Digikey lists them as obsolete
and not in stock. Allied and others do not even list them. Would you
know where some CLC449s may be obtained? National's site has a
cross reference indicating the LMH6207 should replace the CLC449.
But Digikey and others do not list those either.?? I would be willing
try the LMH6207 in spite of the lower bandwidth spec of 750Mhz. vs
the CLC449 bandwidth of 1.1Ghz. if I could only locate some.
Any info would be appreciated.

Thanks

DH
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post #16 of 614 Old 01-08-2003, 08:51 AM
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Hello All

A correction for my previous post. It is National Semiconductor
op amp part # LMH6702MA instead of LMH6207MA. Pin for Pin
Replacement for the CLC409AJE and CLC449AJE op amps.

DH
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post #17 of 614 Old 01-08-2003, 08:52 AM - Thread Starter
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DH,
try this site:

http://www.future-active.com/results...arch=CLC449AJE

I'm not sure if you'll be able to order small quantities, but give them a try. I've not tried the new LMH chip, they're new, being the replacements for the CLC449 chip. A sub company manufactured the CLC line for National, somehow Nation is no longer connected with them.

There are three or more CLC449 or 409 or H1100's on the VIM module. We'll get to that board later.

I'll place an order for the new chip. National had made the claim (before it was distributed) that it would be a better chip.

It's all about the performance... Got Marquee!

 

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post #18 of 614 Old 01-08-2003, 08:57 AM
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If anyone was willing to buy a few of any IC's at once and had trouble finding them, try 'Smith and Associates'. The are chip locators and have found many parts for me I could not find anywhere else. Many things obsolete here are still widely used in China and Russia.

Thanks Mike for starting this thread as I have always wished the 8000/8500/9500 would get the same mod attention the ECP has enjoyed.
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post #19 of 614 Old 01-08-2003, 09:55 AM
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Quote:


Originally posted by mp20748
DH,
try this site:

http://www.future-active.com/results...arch=CLC449AJE

I'm not sure if you'll be able to order small quantities, but give them a try. I've not tried the new LMH chip, they're new, being the replacements for the CLC449 chip. A sub company manufactured the CLC line for National, somehow Nation is no longer connected with them.



Nope. I went to the link and tried to order and the smallest quantity here is 95 pieces. You also have to call to get pricing. I remember some months back that Mike and I were talking about this, and we found a replacement that had the same bandwidth, but I think slew rate was different. Mike, do you have a memory of this? Is this what was different? It's been about 6-8 months ago and I just can't remember what all we discussed.

Thanks a million...Good luck...Let us know... Whichever is appropriate this time! jmwj03 at hotmail dot com
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post #20 of 614 Old 01-08-2003, 11:04 AM
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Analog Devices is crossing it to:

http://www.analog.com/Analog_Root/pr...AD8009,00.html

With double slew rate, but not the same bandwidth.

From Texas Instrument perhaps we can use this 1.2GHz, 4200V/us type:
http://focus.ti.com/docs/prod/produc...tNumber=OPA685
It looks like the best one for the job.

Unfortunately this 2GHz, 9000V/us is a dual type so not pin for pin compatible!
http://focus.ti.com/docs/prod/produc...Number=THS3202

If anyone is interested I have scanned an old service manual for the Marquee 9000 projector.

Kind regards, Claus
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post #21 of 614 Old 01-08-2003, 12:58 PM - Thread Starter
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Guys,
the National Semiconductors true replacement would be "LMH6705" but it has not been released yet, so they are recommending the "LMH6702" as the direct replacement. But I'll not buy that...

Jay,
we were looking at the Max (Texas Semiconductors) replacement. I had the number but cannot find it now.

I still have a few CLC449's in my parts bin (not for sale). Give me about a week and I'll verify a properly functioning replacement.

In the mean time if you have the H1100 it should do fine, but should have a slight HF roll-off somewhere in the upper range/band of frequencies.

It's all about the performance... Got Marquee!

 

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post #22 of 614 Old 01-08-2003, 02:08 PM
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Mike I have some of the 449's (not enough to go around), but I want to be sure that what we are talking here (and in the furture with this thread) will also work fine with no problems on an 8000 model?

I ask because the 8100 parts board I am looking at has the metal Q12 (can't find a Q19) signifying an 'early' board, yet it does not have any blue smt caps. Are all the boards you will be discussing compatible?

------------------------------------

Just a suggestion, but perhaps people wait until near the end of this project and compile a partslist. Then one kind person act as 'the gatherer' and order in the parts since many will have minimum amount requirements. Work out a total on them and sell off kits to do all these mods.
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post #23 of 614 Old 01-08-2003, 03:13 PM
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Mike, I think I found what we were looking at...it was the Maxim (formerly Dallas Semiconductor) of the famed ECP Dallas chip.

Here is the spec sheet on a MAX4224 which they say is the replacement for the CLC449.

http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1718

Anyone care to comment?

Thanks a million...Good luck...Let us know... Whichever is appropriate this time! jmwj03 at hotmail dot com
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post #24 of 614 Old 01-08-2003, 05:14 PM - Thread Starter
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Tester,
you have a very early board. Q19 should be to the right of Q12 (one inch apart). And yes they'll work fine. I got this info from one of Christie Digitals engineers years ago, and I've been using them in the 8000 boards ever since. if the board you have has the metal (TO-5) transistors, and does not have the blue caps, it's probably of the very first ventage. Does your boards have the two white FCC ground connectors?

I'm not sure of the capatibility of the boards, but do know that the later boards will work in any of the previous Marquees.

Jay,
the MAX4224 is a six or ten pin IC, while the CLC449 is a 8 pin chip.

Edit: the MAX4224 does come in 8 pins: MAX4224ESA-ND. Digikey does not have them in stock. I'll do a search for them and order some for evaluation.

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post #25 of 614 Old 01-09-2003, 12:34 AM
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Jay,

The Burr-Brown (TI) part really have MUCH better spec than the Maxim part. You can order 3 pcs. as samples from their homepage. I did that yesterday.
The TI part is better than the CLC449 on some parameters, but not on all.

Kind regards, Claus

PS. The protection double diode on the input is adding both leakage current and capacitance to the video signal. Have you tried to remove it?
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post #26 of 614 Old 01-09-2003, 02:10 AM
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My local Farnell has 6 pieces of NSC CLC449AJE. Price is US$15.94 each and if order more than 25 pieces it will drop to US$10.90 each. It will take 5 days to re-order.
Let me know if I can help.

CH Yeow
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post #27 of 614 Old 01-09-2003, 04:46 AM - Thread Starter
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Quote:


Originally posted by Claus_LM
Jay,

The Burr-Brown (TI) part really have MUCH better spec than the Maxim part. You can order 3 pcs. as samples from their homepage. I did that yesterday.
The TI part is better than the CLC449 on some parameters, but not on all.

Kind regards, Claus

PS. The protection double diode on the input is adding both leakage current and capacitance to the video signal. Have you tried to remove it?

Claus,
I have not tried the OPA685/AD8009 on the neck boards, but I've tried them both on the VIMs. If using on the VIMs the circuit would need redesign, because with the AD8009 I could not get any gain, and with the OPA685 I got too much. But the neck board would not have been my choice to TEST an IC in (tube damage). Though all three chips on paper should have the same gain performance, mainly because the specs are for 150 ohm load, and they are all double gain chips. However, the Marquee video chain is directly coupled after the input coupling cap to the CRT's. Which makes this design a little more complicated than the stand-alone chip in testing.

I've also wondered about the protection diodes, and find it not a good idea for such circuit (video), but never considered playing with that circuit, plus most chip manufacturers put the same diodes in the chip. There are no other form of clamping circuits in the Marquees video chain (agc, limiting, etc), that's what I really like about the design of the video chain, it's very dynamic and direct. The thing that I have also noticed is that on the input section of the VIM, there are two protect diodes on each of the RGB inputs, if you examine that circuit you'll see that great care was used to place those diodes there for protection, while some consideration was giving for maintaining the proper impedance at the BNC. in other words it's not just a basic circuit with protection diodes that makes the proper impedance at the BNC's secondary. so I think that inspite of the protect diodes, some attention has been giving for a truer 75 ohm impedance load at the BNC's on the VIM. Maybe that's something we should look at, maybe there's a better diode that could be used in that circuit without hinderance, because we know that it's doing some hinderance, but on the other hand, if we remove those diodes, what could happen if there was a spike on the input of the VIM or the neck boards - The Marquees have very high power neck boards, there are six Motorola high power RF transistors on each neck board that drives the tube...

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post #28 of 614 Old 01-09-2003, 05:25 AM
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Thanks Mike

I was wondering! Have you looked at the overall voltage level in the video chain through the projector? With your MP-1 (I'm still dreaming about it) you could amplify the video signal at the very start at the video chain, and then we could get a better S/N level through the projector and then lower the gain at the very end in the projector (eg. at the neck board).
Or perhaps Electrohome made a heavy gain at the VIM just to follow the standard input video specs. Maybe it was better to transmit a much higher voltage range and then lower the gain at the VIM. This should prevent the noise being amplified.

I have no idea on how close the video signal is running to the rails, but perhaps they are way off.

Have you tested WHY your MP-1 makes such a difference with a higher voltage swing? Is it because it is bringing the overall video voltage swing closer to max (without raising the noise floor) or what.
Have you tried adjusting the gain up at the MP-1 and then down again at the VIM?


What I'm really going to look at, is lowering the noise floor. With the internal test pictures (all white), low contrast and looking into the tubes, they are so full of picture noise.

I think this is going to be a very exciting thread

Kind regards, Claus
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post #29 of 614 Old 01-09-2003, 06:49 AM - Thread Starter
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Claus,
you raise some very interesting points, I'm glad that you're on board.

I like your idea of lowering the noise in the video chain. I plan to rig up a Marquee just for this, and maybe we can get some of the other masters in the electronic field to join in. There are some very smart people on this forum, but most of them are so humble that they rarely contribute much in these discussions. But I've had the pleasure of speaking with some of them by email and/or on the phone. they're here on AVS, and I would like for them to join us in this. How bout it guys! - Tom Rosbach, jcmccorm to name a few... I'm not an engineer, just a two bit technician, and guy's like this have been very helpful to me in their observations.

Actually the MP-1 works well on a very low output signal. With the jumpers removed, it's in the unity gain state (0.7v in/ 0.7V out). Adding the jumpers puts it in the boost state, and that boost is only 0.7V in to a 0.76 volt out. So there's very little boost, and most people could not notice a difference with the jumpers in or removed. It's doing something special with the signal, maybe I should redesign the whole video chain with the MP-1 design - Hmm! I once had the Mp-1 running at a higher output, it made a Marquee look like a large TV monitor, it was very bright and clear, and that was before clipping. But I thought it would be a little too much on the tubes.

Since I've not tested the Max chip, I've placed some on order (thanks Jay). And for some reason I believe that the Max4224 will probably be the best cross. And maybe National Semiconductor will get that exact cross to production.

I didn't want to get into tweaks, but again, if it comes up let's deal with them with very open minds. let's just avoid the ridiculous...

And Claus, if it's just you, myself and a few others - Let's do this...

It's all about the performance... Got Marquee!

 

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post #30 of 614 Old 01-09-2003, 08:44 AM
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Thanks Mike, I though you where ignoring me

I remember reading about the Marquee wanting 0.9V to perform best. It was either you or Tim. It should produce a more "bright" image, but the whole idea is to lower the control to give the same picture as before, I was just hoping the "amplified" noise would go down with it.

Of course I hope KBK, Tim or Chris would give away some goodies, but I doubt it.
One think I would like a comment on is regarding capacitors and their rated voltage. I once had a very clever college and he told me (said not many people new!) that capacitors only have their rated value very near their rated voltage.
To give an example. Bang & Olufsen is using 10V capacitors on supplies instead of 6.3V. He told me that this is nuts, because a 100uF/6.3V capacitor is near 100uF, but a 100uF/10uF is nowhere near 100uF at 5V! In all the capacitor mod thread I read, I see people changing to much higher voltage and temperature. The temperature is making sense, but perhaps the voltage is not! Of course there need to be "room" for ripple, but that is hopefully a very small amount. Actually that is what we are trying to avoid, but in the power-supply itself it can be big, but not in the decoupling of the power-supply around the board. I just don't know!

I don't even know what parts are on my 9500LC. It is still in its flight case with its melted C-element. I think I can be see the different mods looking directly into the lenses! Then all setup issues is removed from the puzzle.

Kind regards, Claus
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