Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.




2 posts

Wannabe Geek


Topic # 57096 2-Feb-2010 21:25
Send private message

Hello, hope someone can offer help.

In my rally car, I have an intercom (Peltor FMT110) which has an RCA audio output for recording the speech to an external source, in my case a Sony HC42E Handycam.  The problem I have is the sound output from the intercom is very low, therefore I would think I need some type of in-line amplifier.  Here is some info I have found on the net:

The Peltor's FMT-110's claimed output is 20 mV. And there are various standards for line level: +4 dBU for pro stuff = 1.23 Vrms, 0dBm for prosumer stuff = 0.775 Vrms, and -10dBV for most consumer stuff = 0.316 Vrms. So, in general, you probably want about a 20:1 gain preamp, and variable 10:1 - 50:1 gain preamp would be best to allow you to tune the gain to best match the desired levels and sensitivity of your specific camcorder's audio line in.

I didn't know what half of that meant, however the 10:1 - 50:1 gain preamp makes a bit of sense.  So can anyone point me in the direction of such an item, or perhaps offer any advise on boosting the sound output.

Cheers in advance!

Create new topic
3535 posts

Uber Geek
+1 received by user: 125

Trusted

  Reply # 295592 3-Feb-2010 00:05
Send private message

Something like this from Jaycar would probably do the job:

http://www.jaycar.co.nz/produc...

You will need to vary the on-board resistor to reduce the gain. 40dB is 100:1, so is probably more than you want for your Intercom - Handycam project.

The guys at Jaycar are also pretty helpful if you need advice about stuff like this.







2 posts

Wannabe Geek


  Reply # 296170 4-Feb-2010 19:31
Send private message

Thanks Grant K, I will give that a crack and see how it works out. 

Cheers.

Create new topic



Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:



Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:



Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:





News »

New Zealand hits peak broadband data
Posted 18-Jan-2018 12:21


Amazon Echo devices coming to New Zealand early February 2018
Posted 18-Jan-2018 10:53


$3.74 million for new electric vehicles in New Zealand
Posted 17-Jan-2018 11:27


Nova 2i: Value, not excitement from Huawei
Posted 17-Jan-2018 09:02


Less news in Facebook News Feed revamp
Posted 15-Jan-2018 13:15


Australian Government contract awarded to Datacom Connect
Posted 11-Jan-2018 08:37


Why New Zealand needs a chief technology officer
Posted 6-Jan-2018 13:59


Amazon release Silk Browser and Firefox for Fire TV
Posted 21-Dec-2017 13:42


New Chief Technology Officer role created
Posted 19-Dec-2017 22:18


All I want for Christmas is a new EV
Posted 19-Dec-2017 19:54


How clever is this: AI will create 2.3 million jobs by 2020
Posted 19-Dec-2017 19:52


NOW to deploy SD-WAN to regional councils
Posted 19-Dec-2017 19:46


Mobile market competition issues ComCom should watch
Posted 18-Dec-2017 10:52


New Zealand government to create digital advisory group
Posted 16-Dec-2017 08:47


Australia datum changes means whole country moving 1.8 metres north-east
Posted 16-Dec-2017 08:39



Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.



Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.