Jo Tech Service   Joar Falstad


Live audio noise reduction hardware, using a  
strong pass audio filter, with adjustable setting of minimum pass level.
Suitable  in real time background noise reduction systems..

Filter function: 
The weakest parts of the total signal, smaller than the preset minimum pass level,  are removed or redused by a factor.  Up to -20db reduction is used in our filter .

Idea & solution by Joar Falstad.

Read more   /   some video examples :
Real time voice audio background  noise and hiss cleaner ,

Live /  real time  audio voice sound background / ambient noise & hiss reduction / removal  /  cleaner /  filter  /  limiter , 
Unlike a noise gate this system will reduse background noise all the time , also inside a message .

Measured  audio
reduction outside pass level:   up to  100 x  or   20db
audio reduction outside pass level to come.
Strong pass audio filter test  :

Demo video , youtube

Live  audio hiss and background noise reduction ..

What you will hear :
The background noise has almost vanished
The  sound is close to the original.
No time delay or change in pitch and tone balance


Industrial Analog Multiplexer
Detailled schematic examples
0 - 10V  /  4 - 20mA


Idea & design by Joar Falstad

Advanced Public Address System

PC controlled. 
Detailled schematic examples.
ISA demo version download
First ver : ISA  Win95.  
Latest ver :  usb Win7

Advantec USB 48ch DIO interface
and a digital input / output board, also from Advantech


AD/DA Conversion and Data Acquisition made easy.

Time and Masterfile controlled AD-DA conversion ,
Easy setup. Easy to run and control.
The Masterfile
is generated by the program itself , as a linear "Unit Value" function from a Time ref to the next "Unit Value" at the next Time ref.
There is no limit in number of Time ref's  from tne project start time to the final stop time.
PC clock is used to control the Time

First ver : ISA , Win95 .  Early demo version download
Next ver : PCI , Win98 . Plug & Play.
We are now working on a USB ver in Win7



Old news /  history 


DMX  stage lights control    . 
How to connect  & more 

Link to:  
Enttec  compatible  DMX    open source VB6  program download .  1ch. to 512 ch.
 Win 7 + VB6 runtime files + VB6 installed on your computer

Download:   Universal DMX program
download1ch. to 512 ch.
Win 7  + VB6 runtime files
Sony update / service
TA-5650 , drifting bias fix.

Vingtor, Stentofon
Old / obsolete intercom systems.  Replacements. Repairs

Compact 32-2  /  VMP32-2
Old / obsolete intercom systems.  Replacements. Repairs

Zenitel, AlphaCom,  ACM 
Later systems.   Manufactured today .  Also compatible with older wireing and stations.

Monacor Catalog  
We are one of many Monacor suppliers in Norway.


Domain:     ( registered on 20-03-2001

contact:       Joar Falstad

phone:          +47  99718408



Company:     Jo Tech Service  Joar Falstad, Lykkmarka 53, 7081 Sjetnmarka, NORWAY


A big  company has now taken the  same domain name  . " jotech "
To protect our site  and  keep it seen on the internet , we'll  continue to add nice pictures , mostly from Norway.

 Norway , Trondheim

Morning view .
Norway, Lyngen alps  , Havnnes , Rotsund , Nordreisa

Norway, Ekne Falstadberget
Nostalgy from the 70's.  With Vital 15 feet

South Africa .  Cape Town

South Africa .  Cape Town

South Africa .  Cape Town

South Africa .  Cape Town

South Africa .  Cape Town

Norway , Malvik, the ghost tree