I recently experienced a two or three minute power "brown out" which altered my CRT RPTV's (Sony Kp-57WS520) convergence. Some areas were 2-3 clicks off on the convergence grid-- areas near the sides as much as 4 or 5 clicks from being optimal.

My question is, did this brown likely alter anything else such as grayscale or electrostatic focus?

And, if it did alter electrostatic focus, can I re-tweak without it affecting grayscale? I thought only manual focus (on the actual pot) affected grayscale, but not sure.

Kind of sucks since I just had a ISF tune-up less than two months ago.

Time to buy a USP! (any suggestions on brand?)

Yes, get the APC brand. Make sure that the wattage rating is large enough (the wattage rating is less than the VA rating). You have to make sure that the unit is big (VA rating) ehough to power through the brown-outs, probably for at least 15-20 minutes. The APC web site gives you charts which tells you what the rating are. You want the ones that have both battery backup and power conditioning (typically in the $100 to $500 range). See http://www.apc.com/products/category.cfm?id=15.

As for the calibration, you should contact your ISF calibrator and ask him/her. It really depends on what happened to the RPTV power supply. It sounds like you wound up with power supply spiking, which could effect the settings (circuits connectied to the low voltage part of the supply. The convergence is related to what the high voltage supply did (it has less supply filtering than the low voltage sections).

NOTE: I'm a retired EE and have dealt extensively with power supplies.

Thanks, CT. I'll go through their site.

Recently, I came across this Belkin unit - what are your thoughts about it?

http://catalog.belkin.com/pureav_detail.process?product_id=195291

That Belkin one sounds pretty good (if your load is less than 650 Watts - and maybe less than 325W), but Belkin's UPS reputation isn't as good as APC (even though the APC units are slightly more expensive). APC has better quality products, IMHO.

Belkin spends more on fancy cases and APC puts their money into good design, IMHO (again).

My wattage breakdown looks like this:

TV 250
DVD player 40
Receiver 500
In addition, I'd have my cable line to my TV going though - no idea what cables uses.

So, at least 790 watts total...however, I might be adding an HD DVD or Blu-ray player.

Do you think something like 1000 is necessary? It seems like I would have to pay a lot of money for something like this. I guess my other option would be just to get the battery backup for the TV.

The APC production selection tool brought this up for me - stating I need two of them:

http://www.apc.com/resource/include/techspec_index.cfm?base_sku=LE600&fnl=3945,3&fnl_basket=3945,4c

I ended up ordering the Belkin unit linked above. I got a good price on it and will just use the USP portion for my display and DVD player.

David, the APC model you linked to is only a regulator - no battery backup. Yes, the APC models are more expensive, but you get what you pay for. It won't help you in brown-outs - you must have a battery backup for that purpose.

The 500 Watt rating of your Receiver may only be an average (or typical, not a maximum). For example, a 100W/channel, 5.1 channel receiver, would require at least a 750 Watt UPS (it's not USP). Then again, a good receiver shouldn't crap out in a brown-out condition, but it should be connected to a good, high energy (Joules), surge protector.

EDIT: I replied to your PM, too.

Thanks, CT.

I ended up ordering the Belkin unit linked above. I got a good price on it and will just use the USP portion for my display and DVD player.

David -- I am thinking about ordering the same Belkin unit. We have frequent power outages and I want to use it as a UPS for my Sony front projector -- I just want it to stay on long enough to allow me to power the projector off with the remote so that the fan stays on to cool the bulb. Do you know how much power capacity that unit has for sustained operation of a TV? The reason I ask is that I've read Belkin's info and I never see them use the word UPS and it seems to talk about the backup for saving memory but no words about sustained operation of the device.

Thanks,
Peter

Actually, I found other threads indicating this unit will work. I searched before posting, but was looking for "UPS", which didn't help. I find Belkin's information the most arcane of any though -- it states 40 minutes of backup time without any indication of load (most of the others say 8 minutes at half power, 4 minutes at full power, etc).

My only concern is that this Belkin unit is not sine wave - and that sounds like a crucial requirement. Any thoughts?

The manual for the Belkin unit, that Dave refered to, is here: http://www.belkin.com/support/download/files/P74699-A_AP30800-10_AS.pdf. Page 9 states that the output is a "simulated sinewave" +/- 8%. The implication is that this is 100% of the time (otherwise they couldn't regulate the power output).

The manual also states that you should not connect more than 85% of the maximum 640W rating (this means that you should connect no more than 544W). It also states that you should not connect surge protectors to the UPS protected outputs (the other ones already use the internal surge protector).

Other than those caveats, the Belkin unit should work and will cause only minor extra heating in the power supplies of the units connected to it. Remember, in this case, you get what you pay for. The only UPS that I would recommend is the much higher priced APC S15 (provides 33 minutes of backup for around 400W and 8 minutes for 900W) and has a true sinewave output (which is not cheap to build). Note that the APC's S10 unit (as do their lower cost "J" models) also provides a "simulated sinewave" output.

pjp -- Page 9 of the manual also states that it provides 1.5 minutes of backup at 100% load. I assume that the 4 minutes, you refered to, is for the recommended 85% maximum load.

This thread is getting pretty far off the path of this Forum subject - Calibration (I have to plead guilty to its continuation). I think we should probably wrap up this discussion of UPS's here.

The bottom line is that brown-outs can effect the calibration of video components, some more than others. The extent of this effect depends on the quality of the power supplies used (and most are as cheap as possible to get the job done, with very little margin).

pjp -- Page 9 of the manual also states that it provides 1.5 minutes of backup at 100% load. I assume that the 4 minutes, you refered to, is for the recommended 85% maximum load.

Thanks, this helps a lot -- I was looking at the specifications Belkin publishes on the web, not at the owners manual. The 4 minutes/8 minutes was just an example I saw from another UPS (I think Monster) where the power was stated in meaningful terms, unlike Belkin's ambiguous 40 minute time in their spec summary.

I wasn't too concerned about getting a high-end UPS because I only want it for lamp protection, but I guess the simulated sign wave applies all the time, not just during outages, so I may have made a different choice if I'd known this (I already ordered the Belkin). Thanks again for the info -- it was very helpful.