Recording audio into a DVR

[FPVSteve]

Hi,

So I'm using an EMPREX BPR-101 DVR to record my flights and it works great, but I was wondering how I go about recording ground audio so I can do some narration - right now I use my phone but it's a pain having to get the audio files off etc

Right now I have:

• a 3.5mm jack going into the DVR with Composite Video (Yellow) and White (Audio) coming off it.
• These plug into my goggles via the AV out socket on those.
• The DVR records the video from the goggles

All fine - so, I have a white composite wire that I'd like to somehow hook up to a microphone so that the audio going into the DVR is my voice.

Which component do I need to allow me to hook up a 3.5mm microphone so that it sends its audio into the composite lead?

Thanks!

[iPeel]

The DVR is most probably expecting line level audio input whereas a microphone will present much less. There are two options:

Use a microphone with a built-in pre-amplifier.
Use a regular microphone and buy an external pre-amplifier.

You may also be able to use your phone, there may be an app which outputs the microphone straight out to the headphone jack, at about 1/3 volume a headphone will output similar to line level and can then go straight into the DVR.

I had a quick look at the instructions for your DVR and the A/V input didn't mention it could accept a microphone directly.

[iPeel]

Here's an option:

https://www.quasarelectronics.co.uk/Item/cebek-pm-3-mono-pre-amplifier-with-electret-microphone?gclid=CjwKEAjw4dm6BRCQhtzl6Z6N4i0SJADFPu1nIESwsdWznpoxmhN7gteX-RcfpN0HwGNdk8CjjmeAJhoCzZnw_wcB

[iPeel]

Or an even tidgier one from 'merca:

http://www.nghobbies.com/cart/index.php?main_page=product_info&products_id=933#.V1awwFcYIwM

Both will take 12v to feed the circuitry and output line level you can send straight to the RCA audio going to the DVR.

[FPVSteve]

Little bit over my head with the components, I'm plug and play capable :laugh:

Thanks for the help though.

According to the datasheet it says "Audio In: 2 channels stereo input" ... So it will record audio on the composite leads. just need to figure out how to do it :(

[iPeel]

Yes, it will record "audio" but at line level not microphone level which is a different voltage and impedance. What I was providing there were two options that are microphones that output at line level rather than microphone level and take a 2-3s power source which you would have on your ground station.

TBH those boards just need some basic wiring but if you want something simpler you could try Maplins and tell them you want a microphone that outputs line level on an RCA connector, which will then plug straight in to the audio connector on the DVR lead.

[FPVSteve]

Cool thanks I'll have a look on maplins and nip across if I can find anything.

[BlueFlyer]

Just buy a cheap dictaphoner, or use your phone's voice memo function... then copy the mp3 file to your computer and paste it into your editing software.

Surely that's easier than buying special microphones or pre amps or whatever all that was in the posts above lol

[FPVSteve]

I could but I'd like a groundstation where I can just fire up the battery and have it all recording, then it's just one file to copy off the DVR rather than a live video, HD video and faffing around with the phone.

[drambuidhe]

I could but I'd like a groundstation where I can just fire up the battery and have it all recording, then it's just one file to copy off the DVR rather than a live video, HD video and faffing around with the phone.

I'm glad you asked this question because I've been wanting to do the same.
I use the cheapo HK dvr .
If you manage to sort it please let me know how ;D

[BlueFlyer]

Ah, I get you now...  One single possibly big faff, to get it sorted. As opposed to a little faff every time. I see what you mean

[FPVSteve]

It's not just about the faff - the phone I have has a crappy built-in microphone which sounds tinny and is susceptible to wind which spoils any narration - if I can hook up an external mic with a nice little wind blocker than I'll be chuffed. I already have a microphone which I don't use for anything so if nothing else it'd be cool to be able to use it.

Extra bonus reasons though:
a) it requires no extra farting around remembering to press record on my phone.
b) it can power up from the same battery my DVR uses
c) I don't need to have my phone on view of any passers by while i'm in the goggles
d) I don't have an extra wire hanging off me while flying

Having said that I could just hook up my GoPro external microphone and record myself while I'm goggled up - I can keep this in the car boot and record any "evidence" if Tom Twat comes along. But again, it's an extra button press + video clip to merge...

[iPeel]

You seem to be a tricky customer, I don't know whether it was the requirement to attach some wires to three terminals or the lack of case that bothered you.

As a last ditch attempt, how about this:

http://www.ebay.co.uk/itm/HUACAM-HAS04-High-Sensitive-Audio-External-Amplified-Microphone-for-CCTV-Secu-/141937336470?hash=item210c1fe096:g:K9wAAOSw2ENW8a5o

[FPVSteve]

Now that is perfect (well, apart from it being a female connector when I need a male - yet another adapter required).

Thanks!

[iPeel]

Well that would have been the benefit of buying just the board and attaching your own leads stripped from one of the several hundred RCA leads you probably have lying around that came with every piece of AV kit ever bought.