DVR Capacity or When is HD not HD anymore

@Jerry

Strangely enough it's entirely possible that the hard drive did get bigger.  At one time the older DVR boxes all had standard hard drive capacities.  As the drives would fail they would often be replaced with larger drives because it was simply more practical to do so however the firmware in the box would only recognize what it was supposed to based on model#.  We did put out an update some time ago that removed this restriction which caused the older boxes to now all have different capacities.

That is interesting, Chris. But could it have allowed the hard drive to use it's full space, but neglected to allow the diagnostics page to show the new capacity?

Cisco's spec sheet for the 8240HDC lists a 160 GB hard drive able to record and store 20 hours of HD programming. My box was manufactured in November of 2009. It could've had it's drive swapped out before I got it I suppose. Would that information be kept somewhere and accessible with a bar code scan or some other means? 

My hard drive is showing 148.9 GB total capacity with 146.9 GB of that available for recording. It's shown these same numbers since I first got it. It's currently running Passport v. 3.7.061, dated 12-13-2013, which I believe is the date it was created, not the date it downloaded to the box. I got this box in the Spring of 2014 and it got a Passport IPG update later that Summer. The version number changed to the current one at that time.

On one of the more obscure diagnostics pages, Last Reset Info, it shows that on 12-10-15 it received a pass thru message, BSF file has changed, two minutes later it did a Global App swap from PVR to NAV UI, and two seconds after that it reset itself.

If the Global App swap is the update you mentioned the timeframe would fit when I noticed the added capacity. But that still would leave open the question of why it won't show it. It does show used and free space, and these change with each new recording and/or deletion. Perhaps total capacity was set as a constant in the original code, does not read it in real time, and it wouldn't change unless the change was programmed into the new code, which the programmers failed to do. But the used and free add up to the total that is shown so I've come full circle with those two possibilities being mutually exclusive.

I'm just trying to get my head around this. I hate mysteries. Recording time did increase. By at least 30%. The why is the mystery. Whether by an update unleashing it's full potential, which added the new wrinkle that my drive did get bigger, of which I never even remotely considered being possible when I jokingly included the option in my first post, or be it through additional signal compression.

Cisco's stated capacity of 160 GB and 20 hours of HD is probably uncompressed video. So my original 24 hours or so of HD on a 150 GB drive would fit with a compressed signal. And now 32 hours or so on the same 150 GB would fit with Cox going from a 2-to-1 compression to a 3-to-1 compression.

This is not a complaint. The extra recording time is welcome however it occurred. But like I said, I just hate mysteries.

 

 

mpeg2 vs mpeg4 maybe

were any channels converted to mpeg 4?

@Wees41: Great thought! The SA 8240HDCs and 8240HD-DVRs, however, are not MPEG-4 compliant.

Hi Jerry,

My stat sheet for the SA 8240HD-DVR shows a hard drive size of 160GB, providing an estimated SD recording time of 70.1 hours and an HD recording time of 25.6 hours.

Have you considered the possibility that deleted recordings still available in the DVR's Lost & Found menu are interfering with your calculations?

I delete the listings from lost and found everyday when I'm shutting down for the night. The Cisco product data sheet I referenced is from 2007. Outdated information to be sure. Outdated STB as well. EOL was 2010 I believe.

160 GB Internal Hard Drive will store up to 90 hours of SD or 20 hours of HD programs (8240HDC)

That 25.6 hours of HD your specs show was what I had until maybe six months ago. I used 24 hours as a max to give myself a little leeway gauging available space. Right now, I have 31 1/2 hours of HD on my DVR. Something changed. Radically. And yes, I'm sure it's all HD.

There are only two possibilities. More space for data is available on the drive. 30% more. Or there is less data per hour of HD being recorded. 30% less. This increase/decrease is not trivial. Nor an anomaly, rounding error, miscount, or something being overlooked and not accounted for.

I do find it interesting, perhaps even illuminating, but certainly not determinative, that in two responses from moderators, not a peep about my working theory (and only logical explanation IMO) that additional signal compression is the reason. As in, not gonna touch that with a ten foot pole.

Is there any more info on that update that Chris mentioned, name, date, version #? And does anyone know what that Global App swap from PVR to NAV UI that I got in December was all about? Or if it was indeed the update Chris mentioned?

Hi Jerry,

I'm not sure we have the answers you seek. We don't receive detailed information about each set-top box update, and I haven't had any luck finding information about the Global App swap that you found in the 12-10-15 diagnostics. I agree that additional signal compression might explain the mystery; however, we don't have any information about what might have caused this. I'm sorry!