EDIT: Too many users seem to have issues with this recorder. Even though it is a cheap recorder, if it does not perform the basic functions you buy it for, it’s not worth anything. Due to the various issues reported by users, we do not recommend buying this recorder.
There are many options to record the video signal from your Video RX. However, finding one that meets FPV requirements for your Ground Station (“GS”) without breaking the bank continues to be challenging.
Recently, I came across the GDV-101SD miniDVR SD recorder unit by Jetview Electronics which is a new, budget DVR option for FPV. First, the retail price of the unit is a modest $45 USD and a flat $10 shipping from Hong Kong to the US — this may be one of the cheapest SD based video recorders available. Some FVP recording devices can cost as much as $500 and many of these have a built in screen, which may be redundant if you are using Goggles or have a monitor attached to your GS. The miniDVR is best suited for your GS to manage backup recordings of your OSD flight cam picture and with the primary video being recorded by a GoPro or similar HD camera on the plane.
The key draw-backs of this recorder are that there is no hardware button to start recording, it requires the remote for all interactions, and the recorded picture is not a full 30fps. Due to hardware and memory limitations, the recorded picture looks a little bit choppy as the recorder can’t write frames at the full frame rate.
UPDATED 5/19/2011: The unit was recently updated and now supports mono audio recording. The cables that are included now have a single channel RCA audio connection for input. The “output” cable to connect the unit to the monitor now includes stereo audio RCA connections.
The company has how released a miniDVR GDV-101SD User Manual PDF
The miniDVR records a decent “D1” quality picture, but recording compression artifacts are visible. This is not a high quality “HD” recorder and it records in a modest “D1” resolution of 720×480. It also supports recording in “CIF” which is a video resolution of 360×240. The Jetview site does not list the actual NTSC frame sizes correctly. The ones listed here were looked up from the source files played back by Quicktime on a Mac. However, keep in mind that the recorder can’t record at the full frame rate and repeats frames, which produces a video that looks just a tiny bit choppy.
It supports HC SD cards up to 16GB. In my tests I was using a 16GB card an all record and playback functions happened very quickly. The unit comes with a remote, which makes it possible to put the recorder into a case. All you need to be able to get to is the SD card.
The device supports PAL (25fps) and NTSC (30fps) formats. However, as mentioned, the recorder can’t record at these native frame rates and, at least in NTSC, repeats frames. This makes the picture look a little bit choppy.
All detailed specs can be found at the Jetview miniDVR page.
Key benefits for FPV
- Extremely small size
- SD support up to 16GB HC
- 12V DC Power. Most ground stations are powered by 12V, so you won’t need a BEC like you’d need for the FPV specific SD card recorder from Foxtech
- Cheap! This must be one of the cheapest SD card recorders available
- Jetview seems to have them in stock, which can’t be said for other FPV specific gear
- Displays the signal while recording (some DVRs don’t)
- Recorded video signal is not cropped so you won’t loose OSD data
- Has no problem recording through static. Will not stop recording during static, but the picture in my test video did freeze for a few seconds. This freeze means you should likely not use the output signal as your goggle input. The unit does not go to ‘blue screen’ during static. Only shows blue screen if there is no video input at all. See example video.
- Easy one button ‘record’ start/stop via the remote only
- One button ‘screenshot’ which saves a JPG of the input signal
- Remote control
- The “monitor out” cable is a miniplug 4-pin AV cable. However, the video signal comes through the tip of the miniplug, which is not compatible with cables used by ImmersionRC (which carry the video signal on the 3rd ring of the miniplug, counting from the tip of the miniplug)
- The monitor cable that was included in my shipment was faulty. It took a while to figure out why I was not getting any video output. The cable was easily fixed and customized though. Still, QC-ing the cables would be a good idea.
- The unit requires the remote control. No hardware button to start recording, etc. You need a display or goggles to reliably start and stop recording.
- The video signal, during recording, is delayed. So you should never use the recorded source as your goggle input.
- The remote has trouble in direct sunlight. Make sure you operate the remote in a shaded area. We’re still testing good methods to get the remote to work reliably.
- No hardware button to start/stop recording and no visual feedback on the device when recording. Only the recorded picture source will show you that you’re recording. Therefore, you really need a monitor or goggles with a video switch to make starting/stopping recording work reliably.
- Like most DVRs, the recorder will not save a partial file. So if your GS looses power, you will not be able to get the recorded file. There is no file saved on power-loss, not even a partially corrupted file (like the GoPro produces when power is interrupted — due to falling in water, for example).
- The unit can’t produce a full 30fps video. We have no exact details, but our estimate is that each second, the recorder misses a handful of frames, which it makes up for by duplicating certain frames rather than slowing the frame rate. This makes the picture somewhat choppy, but still acceptable for back-up GS recordings. Using a faster SD card will not fix this problem.
Motion Detect Recording
The unit features the ability to start recording on ‘motion detect’. You can set different sensitivities to trigger the recording. The trigger can come from a ‘camera alarm’ which seems to be a camera specific signal available on some security cameras or, more relevant to FPV, on ‘DVR detect’. “DVR detect” means that the miniDVR will check the signal and detect ‘motion’. However, in my tests the recording automatically stops after a maximum of 10 seconds, even if motion continues to be present. There is a gap you can set in between individual ‘motion detect’ events, but the result would be lots of short clips from your flight — not one long clip while motion continues to be present. This feature seems more suitable for security camera type applications, but not so suitable for FPV.
It’s a budget recorder… Don’t expect great picture, totally reliable operation, or ease of use. The unit should be hooked up with a separate monitor to operate the record start/stop. Don’t use this recorder as your Goggle input due to lag and additional OSD data that covers your FPV OSD data. The fact that there is no hardware button to start/stop recording is a real pain and getting remote to operate consistently is also a challenge in direct sunlight. Many users have been getting good results using this recorder for FPV, but be aware of these limitations.
Test D1 Recording
This video was recorded with the “D1” picture quality setting, which is the highest quality supported. The signal was taken with a DX201 Pixim and sent through a 5.8gHz Video TX/RX and routed through an ImmersionRC PowerBox.
Test recording of pure “static”
Download the source AVI of a CIF recording of pure static. Unlike the video of my test video above, this video does not freeze during static recording.
Download AVI of pure static recording.
Demonstration of Onscreen Menu
- “CIF” is a video resolution of 355×288.
- During the video I say that the unit has “2 cameras”. What I meant to say was that the unit has 2 separate ‘camera inputs’. The unit has no camera(s) built in.
- See the section on ‘motion detect’ above
Test picture taken with the ‘screenshot’ feature (720×480 JPEG)
Enable Audio Recording
If you purchase this unit after 5/19/2011, it will support audio recording natively and this mod will not be required!
To enable mono audio recording requires a modified input cable and to modify the PCB board. This should only be attempted if you know how to solder on a PCB board and know how to acquire the necessary parts. I am still looking to get more documentation from Jetview.
See the below pin out for how to construct a cable that will support mono audio recording (this also requires the PCB board modification)
PCB Board Mod
See the picture below for how to modify the board to enable mono audio recording. I’ll try to make this clearer over time.