Portable DVR recommendations?

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g0nzo
Posts: 29
Joined: Tue Oct 20, 2009 6:30 pm

Portable DVR recommendations?

Post by g0nzo » Wed Sep 20, 2017 8:12 am

Any suggestions for a pocket sized SD card DVR, for PAL video?
I am looking for something that will record and playback, and ideally use a file format that I can also view via a PC.
I've looked at ebay and most offerings seem to be aimed at CCTV work. So no idea of hove useable they would be.

Also, I assume that these devices suffer similarly to the LCD monitors, that they only work with clean P5 pics? Anyone got any interesting info on this?

Jules

gus_452000
Posts: 8
Joined: Tue Jun 26, 2012 10:17 am

Re: Portable DVR recommendations?

Post by gus_452000 » Thu Sep 21, 2017 4:06 pm

Hello, I have no association with these sellers or the device's, BUT I have bought and used them
They are on Ebay (other sites sell them as well) the item number is 262782219028
These are built for the FPV guys and record directly to an SD card, they also over come the dreaded BLUE SCREEN issue with LCD monitors.
They allow playback as well as record, and obviously you can remove the SD card and put it into your computer for copying editing.
I warn you now that they are small and very lightweight but do not let this put you off, they work remarkably well.
They are made small and light so that they can be installed into the goggles the FPV guys use.
And they allow an LCD to show noise and upwards i.e. P1 - P5.
A really useful bit of kit and I have installed them into my comtech RX's for when I am out /P or in contest as its just a single button to record.
Hope this helps
regards
Gus M0IKB

g0nzo
Posts: 29
Joined: Tue Oct 20, 2009 6:30 pm

Re: Portable DVR recommendations?

Post by g0nzo » Sun Sep 24, 2017 9:06 am

Gus,

Thanks. Nice find.
For 22quid, well worth a punt.

Just to clarify...
Do they work with video through, whilst recording (and whilst not recording)? So the blue-screen issue is fixed, when watching off air?

Jules.

g8gtz
Posts: 1172
Joined: Wed Apr 07, 2010 6:26 pm

Re: Portable DVR recommendations?

Post by g8gtz » Mon Sep 25, 2017 9:06 am

Hi Jules,

Bought one for £16 from Amazon and can confirm they do have through video when recording or not - looks a bit digitised but is very effective for the price (and size!), does act as a blue screen killer and cleans up the syncs (a bit).

If you are looking for a proper sync reprocessor this is probably worth a look - not bought one yet but kits will be available shortly: https://translate.google.com/translate? ... csmurf2%2F

I've included reference to these and other solutions on the wiki 5.6GHz page https://wiki.batc.tv/5.6_GHz

73 Noel - G8GTZ

gus_452000
Posts: 8
Joined: Tue Jun 26, 2012 10:17 am

Re: Portable DVR recommendations?

Post by gus_452000 » Thu Oct 05, 2017 5:00 pm

Just as a matter of general interest the mini DVR recorder players, will allow around 2hrs 20 minutes of VGA recording on a 4Gb micro SD card, obviously the use of larger cards all the way to 32Gb cards in size increase this recording time considerably.

Although I have an Easy Cap video capture dongle on the home PC which records anything of interest, the mini DVR is actually easier to use in some aspects, for example the ability to start recording at anytime with just a single push of a button (the three control buttons are also available to be wired externally if the unit is placed in a box/receiver). Where as with the Easy Cap, I have to make sure I haven't disconnected the unit from the USB extender lead, and then start the programme before I can start to record.

The mini DVR allow software updates (from time to time, when they have been published) the formatting of the micro SD card whilst in the mini DVR, the play back of video, and also to delete individual video's should you choose to and as previously stated they eliminate the Blue Screen problem with LCD type of displays plus the ability to show noise all the way to a P5 picture. They also appear as also stated to help a little with line synch issue with weaker signals, I have found them very useful.

The only issue's if you wish to think of them as such is the units requires a 5v power supply, which I get around by the use of a small (its almost the same size as the mini DVR) 12v - 5V converter and as the converter will allow voltages from 9v up to 35v input I have no concerns with using it with a car battery when out portable.

The second point is that the unit only has one audio input, when units like the Comtech RX boards have two audio outputs, my simple solution was to simply have a switch that should I find the audio on the other output then I simply switch the mini DVR audio input to the other audio output from the receiver. Although I haven't found use for that simple switch yet, no doubt when out portable one day, it may come in useful and will be a lot quicker than trying to swap audio leads around whilst up a hill in a car park, trying to stop my antenna's from being blown over.

g0nzo
Posts: 29
Joined: Tue Oct 20, 2009 6:30 pm

Re: Portable DVR recommendations?

Post by g0nzo » Fri Oct 06, 2017 8:46 am

Thanks for the info.

On Noel's recommendation, I did order two of them. Have not tried them yet, mainly due to the 5V requirement. I do have a bag of those little step down switching regulators, but need to find them. That is the weekend's job.


Jules

gus_452000
Posts: 8
Joined: Tue Jun 26, 2012 10:17 am

Re: Portable DVR recommendations?

Post by gus_452000 » Sun Oct 08, 2017 10:34 am

Just an update on my findings with the mini DVR units.

Whilst monitoring a 23cm beacon and scanning 13cm ATV (2350 - 2450 Mhz) band yesterday evening (as you do) I noticed around 2432 Mhz what appeared to be some line synch going through the monitor...... hmmm odd not noticed that before, better have a look.

So swinging the dish around I found that quite a bit off from where I was originally beaming to, was a TV sender, sending nothing interesting of note as usual, just channel 4, and in the end I got a reasonable picture through all the wifi that was there as well, colour picture (P3 - P4) and audio!

So being a bit more interested I decided to move the dish back to its original position and take out the mini DVR to see what I could see, and the answer was nothing pure noise, no line synch breaking through the edge of the screen nothing at all. Perhaps the dish is not 100% at where it first was, no, the original 23cm beacon I was monitoring was there (GB3FM) and the Arduino controlled digital compass read the same. So I connected up the mini DVR again and yes there it was the line synch was back again.

So I moved the dish back to the heading for best reception and again P3 - P4 picture (noise from wifi but there, nice and stable) so I removed the mini DVR from the circuit to see what would happen to the picture, and not only did I loose a P point instantly the image had no stability at all, rolling quite badly and not centred in the screen at all.

Now my antenna's are all home brew including the dish itself and inside the loft of the house and the 1.5mtr dish sits in there quite nicely however it is directly above our bedroom (the wife's and I) and a rotator sat on a wooden floor does make some noise as it goes around, and at this point I was asked (told) "did I know what time it was!" So when I get time and the wife isn't in bed I shall try and make some video recordings of this TV sender being received here with and without the mini DVR in line so you can see the difference of them being inline and that of just the raw video signal.

Overall I really am very impressed with the units, I have spent a lot more money in the past and effort on other items in the shack that haven't made as much difference to the picture quality as these, all in all for under £20 or whatever they are selling for now, well worth a go.

g0nzo
Posts: 29
Joined: Tue Oct 20, 2009 6:30 pm

Re: Portable DVR recommendations?

Post by g0nzo » Thu Oct 26, 2017 8:55 am

OK, I finally got around to testing it.
They really do work well. I'm impressed. As a recorder and as a sync processor.

Thanks for the advice all.

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