I'm sure it exists, but does anyone know of a small battery powered box that has a built in speaker and can be used to monitor an audio signal. (Say a XLR, 1/4" ,RCA inputs)
It doesn't need to be loud, just help me fault find across the complex I work at.. (It gets boring lugging around a powered speaker to verify a signal is present)
I could DIY one, but I'm wondering if a cheap alternative exists.
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Audio 'Sniffer' or tester
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Audio 'Sniffer' or tester
Mike de Vrees
Purveyor of old stuff
Purveyor of old stuff
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Futureman - Frequent Contributor

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Re: Audio 'Sniffer' or tester
Use an LM386 Ic. 8 pin chip minimal components needed . Will run off a 9volt battery and drive a 2" speaker at about 1/4 watt. Put a 10k log pot in the input.
http://www.hobby-hour.com/electronics/lm386-power-audio.php
http://www.hobby-hour.com/electronics/lm386-power-audio.php
Alastair Reynolds
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
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Alastair Reynolds - TRM Endorsed

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Re: Audio 'Sniffer' or tester
There has to be half a dozen micro practice guitar amps
About .. About the size of a cigarette pack
Marshalls twins tweeds dunno if they cost much ?
About .. About the size of a cigarette pack
Marshalls twins tweeds dunno if they cost much ?
Rick O'Neil
I think we went to different schools together
turtlerockmastering.com
we listen
I think we went to different schools together
turtlerockmastering.com
we listen
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rick - Moderator

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Re: Audio 'Sniffer' or tester
The Smokey Amp....uses an LM386. could prob test, the wrong impedance...and double up as a battery powered amp that can power a 4x12 as well 

Jamil Khuri
Amusement & Audio Engineer
"it's not awesome unless its 240bpm with distorted 909 kicks!"
Amusement & Audio Engineer
"it's not awesome unless its 240bpm with distorted 909 kicks!"
- jkhuri44
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Re: Audio 'Sniffer' or tester
Whirlwind make a product called a Q-Box
http://whirlwindusa.com/catalog/black-b ... sters/qbox
I used to own one and it was great, lost it somewhere......
http://whirlwindusa.com/catalog/black-b ... sters/qbox
I used to own one and it was great, lost it somewhere......
Dan Fittell
Brisbane, AU
Brisbane, AU
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SYOS - Registered User

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Re: Audio 'Sniffer' or tester
SYOS wrote:Whirlwind make a product called a Q-Box
http://whirlwindusa.com/catalog/black-b ... sters/qbox
I used to own one and it was great, lost it somewhere......
I saw those, but they were outside my price range.. (Around $150 from memory)
I bought one of these off ebay for $7.95
http://www.ebay.com.au/itm/400325572189 ... 1439.l2649
It'll cut down on build time, and I can put it in a diecast box with XLR & Jack & RCA inputs.. sorted.
I had thought about the mini guitar amplifier, but I know it'd eventually get trashed around here.
Cheers.
Mike
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Mike de Vrees
Purveyor of old stuff
Purveyor of old stuff
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Futureman - Frequent Contributor

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Re: Audio 'Sniffer' or tester
Brilliant, you couldn't buy the parts for that let alone a PCB as well.good solution,maybe chuck a little 600 ohm to 10 k transformer in front on the xlr and the RCA straight into the input.
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Alastair Reynolds - TRM Endorsed

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Re: Audio 'Sniffer' or tester
For a totally passive solution, find an old 802 style Telecom phone and use the receiver (earpiece). It will work on line level signals, is portable and doesn't require batteries.
David Kilpatrick
Sydney, AUS
Sydney, AUS
- davek
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Re: Audio 'Sniffer' or tester
A small multi-meter is handy too for simple connectivity / voltage tests - no audio in my old VU version though 

Ian Dare
- Drumstruck
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