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Reviews Categories | Filters, Audio: (DSP and others) | Idiom Press SCAF-1 Help

Reviews Summary for Idiom Press SCAF-1
Idiom Press SCAF-1 Reviews: 91 Average rating: 4.7/5 MSRP: $89.95
Description: The new SCAF-1 filter from 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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KJ6ETL Rating: 3/5 Apr 19, 2012 17:43 Send this review to a friend
Good product, no support  Time owned: 0 to 3 months
I have built only a few kits and am by no means a true ham with the “knack”. To me building a kit is like putting a puzzle together with at the end a piece of equipment that I can actually use.

The kit arrived quickly, all parts were counted for. A professional made printed circuit board a case are almost a guarantee to end with professional looking device. The manual is well written but it certainly could use a few images to shed a light on some parts of the construction. In particular the wiring is very hard to follow. Further I made a mistake by soldering the diodes in exactly the wrong directly as the should have been. This leads to my main complaint of this kit. There is no support. During the build I wasn’t clear about the diodes and despite reading the instructions carefully I was not 100% sure and decided to pause the project and call Idiom Press. I left a voicemail and have yet to receive a call back :-(

After I connected all the wires and turned the filter on I could not hear any difference in the audio. I started to look for clues and verified all the connections. In the hope that an expert might spot my mistake(s) easily I send a number off pictures to Idiom Press in the hope to receive some support. Until today the email has remained unanswered :-(

I ended up removing the circuit board from the wiring and started the diagnostics with a minimal system set-up. It turned out that the fault was on the circuit board and not the wiring. Since I had trouble understanding how the diodes were supposed to be mounted I painfully extracted the parts and put them back in the reversed direction. Voila it works

This filter does a great job cleaning up CW signals. Together with the 250 kHz narrow CW filter I can easily decode signals that where otherwise very hard to detect. On SSB however the effect is less noticeable.
GM0WNR Rating: 5/5 Feb 10, 2012 11:23 Send this review to a friend
Great little bit of kit.  Time owned: 0 to 3 months
This is one of these pieces of kit that, once you've got it, you can't remember how got by without it! Firstly, the kit is very easy to put together, with very well written, clear, step by step instructions. If you are careful and take your time you will end up with a very neat looking addition to the shack which works first time, as mine did. A user manual is really not needed as there are only 2 controls on the front of the unit, and one of these is the on/off switch! Basically, regardless of mode, you just turn the "width" controller till you get a pleasant sounding result, whether that be SSB or CW, which is my favourite mode, and in this mode, the filter excells. In my humble opinion this filter is as good as any I have tried, and I have tried a few, including a DSP filter by MFJ, an audio filter by Diawa and a couple of Datong FL-3's, remember it is not a crystal filter, but it does not claim to be, it does a very good job of filtering out unwanted signals. I would rate this as a must have for CW ops. All in all, a great sounding, useful, and, most importantly, a nice looking bit of kit that gives you the satisfaction of knowing you built it with your own fair hand.

KG7RS Rating: 5/5 Jan 13, 2012 23:10 Send this review to a friend
Attention Boatanchor Ops!  Time owned: 0 to 3 months
Hi Folks,

I've been aware of the SCAF-1 for some time but doubted the effectiveness of an audio filter to improve CW selectivity. During a recent kit building binge, I decided to try one for use at my vintage station with a Hammarlund HQ-160 receiver. What a difference! The HQ-160 isn't noted as a selectivity champ but does have a very effective slot (notch) filter and a Q-multiplier which can provide decent selectivity when properly adjusted. Still, it requires lots of knob twisting and nudging to attain usable CW selectivity. With the SCAF-1 switched in the difference is profound. The passband is quickly and easily narrowed with one knob. Signals really stand out and copy is considerably improved. Very strong, very close signals may still cause desensitization - after all, this is only an audio filter, but I've found the HQ-160's slot filter placed right on top of the offending signal takes care of it. Using the slot filter without the SCAF-1 still allows the offending signal to be heard; with the SCAF-1 and notch, the offending signal is gone. Most often, the SCAF-1 alone is all that's required to provide the necessary selectivity for single-signal reception.

SSB readability is also greatly improved at the widest setting of the passband knob on the SCAF-1. The HQ-160 passband is so wide that just switching in the SCAF-1 makes a substantial difference in readability.

I'm thrilled with this product. I love to operate vintage equipment, especially on CW, and the SCAF-1 makes all the difference. Best of all, I can use it to clean up the selectivity of just about any old boatanchor receiver I may want to play with. In combination with the HQ-160 with its slot filter, the result is a very competent CW receiver which was only average before the SCAF-1 was installed. The SCAF-1 removes much of the suffering of trying to copy CW with less capable boatanchors such as an NC-88, SX-99, etc.

My SCAF-1 came as a kit which required about 6 hours to assemble including inventory & sorting/organizing the parts. Assembly instructions are well written. The kit uses several discrete wires connecting the DPDT toggle switch, passband pot and the audio input & output jacks which slows down the building process a bit. Otherwise, assembly is straightforward and shouldn't pose any difficulty. This would be a good kit for a first-time builder. The kit includes a very high quality two-piece cabinet which is pre-drilled and nicely labeled on the front panel. The rear panel has no labels oddly enough. Audio input from the radio is an RCA jack. There are 1/4" and 1/8" output jacks and the builder has a choice of which is used for a speaker or headphones. The output jacks may also be wired as stereo (3 conductor) or mono (2 conductor) plugs. 12VDC power input is provided through a 5.5 x 2.1mm standard coaxial jack. I used a 12V 1A regulated wall-wart from Jameco which uses a built-in 3-terminal regulator IC, ample filtering and provides a stable 12.6VDC source. Otherwise 12-13.8VDC station power may be used. The unit is very small and easily integrates into an existing setup.

If you're a CW op and love to play with vintage/antique gear, I hope you try the SCAF-1. I can see how this product may not make a profound difference when used with modern equipment with already good selectivity but with vintage equipment, the result is astounding.

73, John, KG7RS
HFHAM2 Rating: 3/5 Nov 25, 2011 15:11 Send this review to a friend
Okay but not Great IMO  Time owned: 0 to 3 months
I wasn't as impressed as everyone else seems to be with my SCAF-1. Yes, it works okay, but doesn't go very narrow for CW work. For SSB, if you adjust it narrow enough to make a difference, it makes the voices muffled (which I hate listening to).

Maybe I was spoiled with the SCAF on the SGC SG-2020 HF transceiver which would narrow right down to 100Hz for single signal CW copy (fantastic), but the SCAF-1 doesn't go that narrow.

After a month or two of using it, I sold it and bought a 250Hz crystal CW filter instead (which did a far better job on CW).

The samples on the Idiom Press web site sound great, but I didn't get results as good as those.
VE3GNU Rating: 5/5 Feb 7, 2011 10:52 Send this review to a friend
Perfect  Time owned: 0 to 3 months
There are a goodly number of Audio-type filters available, but after considering, and then discarding some of the candidates I finally, and happily settled on the Idiom SCAF-1. It's a perfect addition to my Ten Tec Argonaut V; it does exactly what is advertised and delivers the kind of listening comfort, that I feel, is welcome in today's DSP environment. As well, the EHAM REVIEWS were instrumental in acting on my choice, and if I may suggest---anyone with a DSP rig might want to consider this option for a more relaxed and pleasurable listening experience. I might add that this was my third dealings with Idiom Press---great products, great service, and a great company.
N4UE Rating: 5/5 Jan 11, 2011 13:59 Send this review to a friend
LID remover!  Time owned: more than 12 months
Hi. A great deal of the time while at my PC, I have my FRG-7 running. I have all the Kiwa mods and think very highly of this receiver.

A LOT of the time, I listen to the 'stuff' on 14.275. It seems like everyone tunes up there or QRMs the other stations just for fun.

Today, there were a lot of carriers around that trequency. I found that the SCAF-1 removes those hetrodynes almost as good as the 'Notch' in my 756PRO. The Automatic Notch in the PRO never ceases to amaze me!

I helped Idiom Press with the Manual several years ago and I have my NR knob wired to increase the NR as the knob is turned CW.

It is also excellent for removing the bleed-over from nearby stations.

I can't believe how well this little box works for the $ !!

NG9D Rating: 5/5 Nov 8, 2010 04:39 Send this review to a friend
Clean low-pass filtering  Time owned: 0 to 3 months
My IC703 has a stock SSB filter, and for CW sometimes the CW-reverse feature and IF-shift don't provide enough selectivity. The SCAF-1 is a useful and economical low-pass active audio filter. The kit is easy to assemble and does definitely provide clean low-pass filtering, you can see it assembled and hear how it works at The recording is from this weekends CW contest. Kit ordered last Wed, delivered Fri and assembled and tested over the weekend. 73 de NG9D
WF8O Rating: 5/5 Oct 21, 2010 05:20 Send this review to a friend
Outstanding!  Time owned: 0 to 3 months
I read all I could online about this filter. I was skeptical of the consistent accolades this low pass filter receives. I got mine last Friday in three days from the manufacturer. I must say that the unit is a qrn killer on CW. I have 500hz filter and I have Yaesu DSP built into my 857. Those are nice, but the "go to" remedy for qrn and qrm is the Scaf-1. Narrow filters raise the apparent noise level, and DSP has its drawbacks also. The SCAF-1 provides the ability to pull weak stations out of the grass and to copy them without fatigue. It's outstanding!


Mike Narges WF8O
KG3Z Rating: 5/5 Mar 13, 2010 13:51 Send this review to a friend
Excellent kit, and support  Time owned: 0 to 3 months
I use a Kenwood TS-520 & TS-530, and wanted to reduce the tiresome noise on SSB and CW. I found the SCAF-1, and gave Rob W7GH a call at Idiompress..a year ago. Rob spent time explaining the SCAF-1, how well it performed, BUT suggested I install a crystal filter before purchasing the SCAF-1. Rob went so far as to give me the suggested filter part number at INRAD, and I followed his advice. The crystal filter worked well, but as I listened to more and more CW, the howl was very fatiguing. Remembering how helpful Rob was in talking me out of his product originally, I purchased the SCAF-1 kit.
The kit arrived carefully wrapped and packed, with all parts accounted for..nothing missing. The instructions left nothing to the imagination; a casual observer could complete the kit. The sequence was exactly as it should be: a very logical order. Anyone with Heath, Knight, EICO, RCA etc, etc kit experience won't have any trouble.
The unit powered up without any trouble, and in less than 5 minutes I was ready to try copying code. It actually took more time to decide where to put it than to adjust it. Functionally, it makes a great difference in SSB as well as CW, reducing fatigue quite a bit. I have mine cabled to cascade thru my SP-230 which gives me more filtration, although I doubt that will be necessary--the SCAF-1 works beautifully.
VK7JB Rating: 5/5 Feb 16, 2010 03:29 Send this review to a friend
Another gem by Idiom Press  Time owned: 0 to 3 months
All the hallmarks of a great kit: Excellent, prompt customer service. Quality components - and no missing parts! Unambiguous instructions. Perfect function, exactly as described. What more can you ask for? Just like the Logikit CMOS-4 keyer kit, the SCAF-1 kit was a dream to construct. It has transformed my CW listening experience and added another level of control over SSB audio. I've found it works very well with the DSP on my IC 746-pro, which on its own, I'd never found very useful. I've retired an expensive outboard/inline DSP unit - the SCAF-1 and onboard DSP combo is so much more effective. Thank you Idiom Press for another gem.
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