Cooling Fans in most RPTVs? (1 Viewer)

[Arthur S]

I found out that there are fans in the Hitachi S700 series and the noise in quiet scenes is enough to drown out dialogue. How common are fans in RPTVs?

Is it only for those that have a HD Decoder built in?

Thanks

Artie

 

[Neil White]

There's an HD decoder in my Sony KDP-57WS550 and no fan as far as I'm aware.

N

 

[JimmyJK]

most in my experience are the 80 mm flavor fans Ialways switch them out with panaflo L1A's whisper quite and have great CFM.

 

[Steve Schaffer]

Arthur,

DLP and LCD based rptv's use a high-intensity bulb to produce light which shines thru the lcd or dlp panels to produce a picture. These bulbs produce a lot of heat and thus need cooling fans.

DLP sets also contain a motor driven color wheel, which may also produce some noise.

CRT based rptv's don't use cooling fans, as they use an array of 3 cathode ray tubes to produce the picture. These are "liquid cooled" and don't require fans.

 

[Arthur S]

Steve

The Hitachi s700 series are CRT based and there is a thread out there where people who bought s700 models actually saw the fan when the tech came to check out the noise.

Again, my guess is that it is needed to cool the built-in HD Decoder. If I am not mistaken, the short lived RCA 38" had a fan, and they were told by RCA it was there to cool the HD Decoder box.

I wish I were wrong about this cause the ones with the HD Decoder built-in only cost about $50 more than the same model without the decoder.

Thanks

Artie

 

[Steve Schaffer]

Artie,

My bad. You are probably correct in assuming the fan is there to cool the HD tuner.

I could be wrong but I was under the impression that the built-in Hitachi HD tuners were ota-only, in which case you would still need a cable or satellite box to get any HD content other than the broadcast networks (i.e. HBO, Showtime, Cinemax, ESPNHD, Discovery HD, HDNet, INHD, etc. would not be available on the set's tuner).

The built in ota HD tuners will not tune cable HD, which uses a different broadcast standard vs ota channels.

 

[Arthur S]

Steve

My understanding is that the Hitachis can handle HD Cable feeds unless the cable signal is scrambled.

Thanks

Atie