Kitted and Offered For Sale By The Four State QRP Group
Designed by David Cripe, NMØS
Click photo for Larger Image
The HI-PER-MITE is a HIgh-PERformance SMALL audio filter.
It is designed to be very versatile, have low parts count, be inexpensive, yet provide outstanding performance.
This is a flexible design that can be used as a stand-alone unit driving headphones, earbuds, or speakers, or it can be easily integrated into an existing receiver needing additional CW filtering (see manual for details).
Designed by David Cripe NMØS, it features a 200 cycle bandwidth with NO RINGING! It can be used as an external stand-alone unit with an onboard audio amp for driving a speaker or headphones.
It also can be built into a receiver without using the audio amp, or with it if you need an audio stage.
This is a very useful accessory for direct conversion or other rigs needing additional selectivity.
It removes/reduces signals and noise outside the 200HZ passband, and also power line hum in Direct Conversion receivers.
Thus providing comfortable listening while using earbuds, headphones, or a speaker.
If you have a direct conversion receiver, you will love this filter.
The HI-PER-MITE is a much improved version of Dave's HI-PER Audio Filter circuit that was published in the May 1994 issue of 73 magazine.
If you wish to learn more about the genesis of the HI-PER Mite, and learn about important audio filter design parameters, click on the original 73 article link in the documentation section below.
This low cost kit sacrifices nothing in the way of quality.
It features a high quality printed circuit board, low parts count, all through hole parts, and fast and easy building.
It is an excellent kit for first time builders, and was chosen as the Buildathon kit for OzarkCon 2012.
First time builders please note: This kit is not difficult to build, there are NO SMT parts and the parts are wide spaced on the board making installation easy.
Specifications and Design Features
Bandwidth:
200 cycles at the -3 DB bandwith points.
Center Frequency:
The center frequency in the passband is 700 HZ
Signal Gain:
0 dB to 50 dB, user selectable
No Ringing or Buzz:
Nice, smooth audio - care has been taken in
the design to eliminate ringing.
Versatile:
Drives speaker, earbuds, or headphones.
Use standalone or install inside rig.
Audio Power:
500 mW into 8 ohms, from 9v supply
DC Power:
5 to 13 VDC at less than 15 mA
NO SMT Parts:
All through hole parts..
NO Toroids:
There are no toroids to wind, special
circuits simulate them.
PCB:
High Quality, silk screened, two sided 2.2" x 1.5" PCB.
•
Note to Canadian Purchasers:
Due to high bank processing fees,
we can no longer accept Canadian Money Orders.
•
If paying by check or money order (US $ only)
please make it out to "Four State QRP Group" in the
amount of $28.65 for each kit purchased,
and mail to:
Four State QRP Group
Johnny Matlock ACØBQ
379 23rd Road
Lebo, Ks 66856
The HI-PER-MITE is carefully kitted and shipped by
Gene Sylls, KG6EYE
Please direct shipping, kit, and part related questions to Gene Sylls
All proceeds are applied toward funding OzarkCon. Thank you for supporting The Four State QRP Group.
The files
and images on this site unless otherwise noted are copyright by the
Four State QRP Group and may not be published or used without
permission.