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Reviews For: Idiom Press/Ham Supply SCAF-1

Category: Filters, Audio: (DSP and others)

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Review Summary For : Idiom Press/Ham Supply SCAF-1
Reviews: 93MSRP: 108.95 kit 148.95 assembled
The new SCAF-1 filter from Ham Supply/Idiom Press makes your radio listener friendly, whether you are an SSB or CW operator. Using a modern but little known technology called SCAF filtering, the SCAF-1 is an active audio low pass filter offering user control of the filter cut-off frequency, yielding a stunning 96dB per octave roll-off of signals above the cut off frequency, and no white noise. It is the perfect partner for your crystal or mechanical filters. And, unlike most audio filters, there is absolutely NO ringing.
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
KY6R Rating: 2003-06-26
Improves TS-2000 Time Owned: 0 to 3 months.
I wanted to see if I could take my Kenwood TS-2000 and get that same "signals seem to pop out of nowhere" sound that I get with my Ten Tec Omni V. The SCAF-1 is exactly what was needed - and it takes the TS-2000's hot front end and lets you filter out the noise. Takes the "fatigue" out of working CW with the TS-2000.
K9RB Rating: 2003-06-21
Fantastic Device! Time Owned: 0 to 3 months.
The SCAF-1 is a well designed unit utilizing high quality components and well written assembly instructions, making the kit a pleasure to assemble and wire for anyone with kit experience. The real joy is the finished products performance. It virtually eliminates white noise and makes weak signals much more readable, ever with relatively modern DSP rigs! It really is an asset to the DX'er trying to dig signals out of the mud and hash. It's range of operation works on CW as well as SSB, including apparent S/N ratio improvements as well on the digital modes. This filter excels in bringing the signal out of the background noise better than any other filter I have tried. I own two Autek's QF-1 and QF-1A, A Clear Speech Base unit, A Radio Shack DSP, and a J-Com and this amazing SCAF-1 puts them all as "also rans" with its effectiveness and simplicity of operation. IN and Out switch and one knob that adjusts the low cut frequency. It's really suprising how effective this unit is. I've used it with both my TS-950SDX and my Omni VI Plus and it works equally well with both these supurb rigs. I'm thinking of ordering a second unit to use in conjunction with my IC706MKIIG in my mobile installation. The kit was a fun project, but if thats not your idea of fun, a factory wired uuit is also available. Definitely a worthwhile accessory to any station where the elimination of tiring white noise and easier copy of weak signals is part of your operating desires. I highly recommend this unit. Rog-K9RB
W0FM Rating: 2003-06-04
Simplicity at its best! Time Owned: 0 to 3 months.
I finished building my SCAF-1 yesterday and put it through its paces all last night. I'll have to say that its simplicity of operation can quickly become habit forming. I soon found myself reaching for the knob on the SCAF-1 before any others on my feature-rich transceiver.

The kit is high quality, typical of Idiom Press' LogiKits. The SCAF-1 features the same beefy housing as my CMOS-4 Keyer. The instruction manual is excellent and left me scratching my head only once. The order of assembly is logical and well thought out. All components worked and measured within tolerance right out of the box which speaks to Idiom Press' quality control.

Other posters noted the lack of silk screen labeling of the rear panel connectors. While no doubt a cost-saving consideration, it's also important to note that the 3.5mm and 1/4" phone jacks can have alternate assignments (Speaker or Headphones) with the builder making that selection during construction. Therefore, under the circumstances, I don't see how LogiKit could label those two jacks, so why waste money on labeling just "Power" and "Audio IN"?

Performance wise, I found that my SCAF-1 filter greatly reduced or cancelled most any annoying audio going to my speaker or headphones and surely made operating less fatiguing. I was pleased to find that it lacked the "watery" sound of some of the digital audio filters I have purchased and ultimately sold. Clarity of the desired audio, both CW and SSB, remained surprisingly good for the most part, and even enhanced at times. I found that the .WAV samples on the Idiom Press website are accurate reprsentations of the audio improvements that I have experienced with the SCAF-1.

I have only one VERY minor suggestion for the folks at Idiom Press. The 12VDC power connector on the rear panel is a 2.5mm coaxial DC jack. I wish they had include the matching 2.5mm coaxial PLUG in the kit. That turned out to be the only size I didn't have on hand when I finished the kit. Not much added expense there and it sure would have saved me a trip to Radio Shack when (I thought) the project was done.

Simple as it is, this nice filter certainly has found a home in my shack. And, thanks Idiom Press for supporting my kit-building habit. Keep 'em coming!

73, Terry, WØFM
N1LQ Rating: 2003-06-02
Simple, Elegant, Effective Time Owned: 0 to 3 months.
A fun and easy kit to assemble. Deceptively simple to use. Frequently more effective than DSP or analog IF filtering. A valuable addition to both CW and(to my surprise)SSB operation. The CMOS-4 keyer and the SCAF-1 filter are two of the best after-market accessories around. Check out the audio files at Idiom Press's web site for a demo. Great Stuff!
KF0KA Rating: 2003-05-28
Better than i expected Time Owned: 0 to 3 months.
I ordered it on monday, and it was in my mail on saturday. I built it sunday and started playing with it. I have it hooked up to my scout, that has what Ten Tec calls a jones filter. i always thought the filter in the scout was good for a low end rig.This SCAF filter is better....MUCH better. I have only used it on CW, but thats about all i do, so thats fine with me. This is a really nice product.

N8SHZ Rating: 2003-05-28
Excellent addition to FT-1000D Time Owned: 3 to 6 months.
I thought I had a super set up until I bought the Scaf-1. Plenty of other external filtering I thought, but weak signals with lots of noise were impossible. Now I just turn the knob and eliminate the QRM and racket. 15 new CW countries since I got the filter, 15 to add to my 233 ARRL and 275 logged. SSB is a dream as well, as it allows easy adjustment of the receive band width and can work in between any of the internal filters I have. Great Job guy's!
W0FG Rating: 2003-05-26
Simply Elegant - Elegantly Simple Time Owned: 0 to 3 months.
I like audio filters. I've used a Bencher XZ-2 for more years than I can remember, so when a good friend showed me the new LogiKit SCAF-1 and told me it was a Bob Locher project, I knew immediately that I had to have one. Having now had a couple of hours to fool with it, I know it was the right decision. This is simply the slickest little audio filter I've ever used. It has absolutely no bells and whistles. It does one thing and it does it superbly. That one thing is being a low-pass filter. The only control (aside from the on/off switch) is a pot which lets you dial out the high-frequency component of a signal to eliminate white noise or high-pitched QRM. I'm a 99.9% CW operator, but in the interest of fairness, I did try the SCAF-1 on SSB. I like the reduced high-frequency response there too, but it's on CW where it really shines. It's simply amazing the way it knocks out noise and high-side QRM, even with the narrow (500hz) filter engaged on my FT757. The Telex Twinset headphones I use are 35 years old and an artifact of my days as a Navy CT. I wished I'd had a SCAF-1 back then between them and the R390's!! Another great job, Bob. Thank you very much.
K7ZD Rating: 2003-05-20
Fatigue-buster! Time Owned: 0 to 3 months.
I had a older SCAF filter in the past that did a
good job, but the RF filtering and general construction quality left a lot to be desired. When I saw this little unit I had to try it.. and as others have stated, it just works great. The key use in the shack here is to reduce the fatigue caused by receiver hiss. Suggestions would be to make another model that includes audio peaking for CW, and to silkscreen the panels. 73, Gary
WB5PLJ Rating: 2003-04-21
Worth the money Time Owned: 0 to 3 months.
This was an interesting kit to build and a useful filter to have. The kit took me a couple of hours to build and was relatively easy to do. The manual is well written though slightly less perfect than the CMOS4 manual. The filter it's self is quite interesting and at times there is nothing else that will work as well.
VE3RPF Rating: 2003-03-27
Effective Filter Time Owned: N.A.
I recently purchased a kit called the SCAF-1. I built it in 4hrs and tried
it out with my K2 and K1 and am really impressed with the results.

The SCAF-1 is an outboard audio filter that has a pot for adjusting the BW of the audio with at least 90dB skirts. The SCAF-1 virtually eliminates white noise and most hetrodynes as well as narrows the BW of the signal to eliminate interfering stations in the same
passband. Super on CW!

There was an older version of this called the Super SCAF and although very effective, it used BCD wheels making quick adjustment more of a chore.

The SCAF-1 is as easy as turning the pot to your desired BW. Now I keep saying BW even though it's advertised as a lowpass filter. Both terms are correct since the SCAF is designed so that frquencies below 120Hz are greatly attenuated. So it's like having a Band Pass filter with the lower frequency setting fixed and varying the higher frequencies.

Here's how it was described to me in an email to Logikit:

"Actually, the filter is primarily designed as a variable low pass filter - but there is also some fixed high pass filtering to roll off the low frequencies as well. The input to the filter offers some filtering. Also, C-19 further limits the low frequency - this capacitor was originally a 4.7 Ufd but we did some experimenting and found we got a huge improvement in the low frequency roll off by going to the .01 cap. Getting rid or at least greatly reducing 120 hertz power supply noise was a part of that goal and we think we got it pretty well."

This filter works great!
You gotta get one.
You won't be disappointed!