Amplifier and Enclosure Kit for LASERBEAM-DUAL Filter Modules (DSP module included) - (BOXA-DUAL)
Also available built:- DSP Audio Filter Unit
The popular LASERBEAM-DUAL filters are ideal for incorporating into your own designs. However, for additional flexibility we have designed this great amplifier/enclosure kit which will allow your LASERBEAM-DUAL filter module (included) to be used with all your favourite radios. It has a professional look to compliment your shack.
The BOXA-DUAL kit consists of a PCB that the filter module (included) will plug into, together with an audio amplifier. The front panel features the CW Tuning LED (Sig) and Overload LED (Lvl) as well as a bandwidth switch (W/N) and volume control (Vol). The rear panel has 3.5 mm stereo sockets for audio in and out as well as a power socket for a DC supply (5-15 Volts).
As supplied, the board will drive headphones or a small loudspeaker. By changing two resistors, audio output can be increased up to 1.5 Watts which will drive loudspeaker. Because the filter module is a plug-in unit you can swap between different LASERBEAM-DUAL modules depending on your application.
The BOXA-DUAL enclosure has laser-cut gold-effect panels which screw into a rugged aluminium case. Power input is via 2.1 mm power socket (plug supplied).
The kit uses all through-hole components and is an easy build for a beginner. Build time about 40 minutes. Click here for instructions.
Note that the filter modules are bandpass filters only, so will not do anything about noise inside the passband. However, they should be very effective at eliminating noise and signals outside the passband. They will make the biggest difference to older or simpler radios that do not already have advanced DSP filtering on the audio output.
A 3.5 mm to 3.5 mm jack to jack lead might be handy. Click here.
Cable for your power lead could be useful. Click here.
A 3.5mm mono to 3.5mm stereo adapter is required to connect speakers or headphones with a mono plug to this unit, which has a stereo output (plugging in a 3.5mm mono plug without an adapter will cause a short circuit and reduced audio output volume). Click here
If powering this filter from the same power supply as your radio, you may need a ground loop isolator. Click here.
Size: 85 x 63 x 30 mm
Weight: 136 grams
Supply Voltage: 6 - 15 Volts (minimum supply voltage increased to 6V as of early 2022 due to component changes, was originally 5V minimum)
Current: 70 mA - using headphones
Power output: 1.5 Watts maximum into 8 Ohms (maximum depends on internal resistor values)
Also available from our international agent(s):
19 Reviews Hide Reviews Show Reviews
First class service from SotaBeams. I ordered the filter and it arrived in the post next day at 10:30 so set about building and by 12pm was testing it on my Yaesu FT818ND. Wow, this thing really works exceptionally well at reducing noise particularly for CW and filtering out other stations operating on frequency nearby.
Very pleased with the operation. A great help when needed to pull in the cw signal when local noise interferes.
I have bought two of these in the last year or so. Excellent kit that went together perfectly well and transformed my listening pleasure with an Icom R71 and NRD525 on 40, 60 & 80m CW. Strongly recommend the narrow CW filter to anyone using a RX without IF CW filters and no DSP. The kit really makes a difference!
With very little experience, I was able to build this kit in under 2 hours. It works great with my FT-817 and homebrew rigs. It can even clean up the receiver audio of a Pixie! I have also used it in-line with my interface working digital modes and it has made a huge difference in the waterfall. Great product!
I dropped hints to the family of what would be a good Xmas and birthday pressy...glad I did...easy to build with good instructions and makes cw copy on the 817 very pleasant ....thanks richard... Hint ...do a test run with self tappers before affixing the end plates as screws are tight and easy to slip and scratch panel with driver.
A loth of cw operators like me have experienced fatique when listening to kx3 rig on cw for longer periodes. This have been very irritating when considering the price of the rig and that cw is one of the main modes for low power operation. I got the idea to try to use the Laserbeam-Dual on the rig. It turns out that I am much less fatigued after 1 or 2 houers with listening. I manipulate the origional filter and the 2 position cw filter on the Laserbeam-Dual trying to decrease the noise as much as possible. Quit easy when You get into it. To have an audio amplifier is important because the build in audio amplifier is a bit weak on kx3 when driving an external audiofilter
Amazing. Using digital filters you can usually expect a delay between in and out. That one is here less than approx. 10 ms, which is an excellent value. Digital devices most of all have their own RF emission across the shortwave bands due to MCU clock rate, which one is here so low, you could hard identify by sensitive measurements. Thus DX shortwave reception on testing never was affected by unwanted MCU clock emission using that device. The related noise on AF-output is extremely low on amplifier output, you cannot hear. It seems an internal limiter is always working in the background, you do not notice on normal operation, but what is a good extra feature. In comparison to "normal" OP-Amp filters, there are no distortions caused on resonance peaks. The quality of kit components is outstanding. The service contact is excellent, too, by the way.
Great to have a well designed enclosure kit which included a small audio amplifier
Have had the filter a few weeks and have been using it with my IC703 both in the shack and portable. Durning our QRP groups outings the guys can't believe the single signal copy on CW. The only minus is it draws about 200mA and can kill a 9V battery overnight if you forget to unplug it 73, Jim KI1H
I was originally going to put the SOTABeams filter module directly into the FT-817. But then I realized I wanted more flexibility than having it permanently installed in there, even though it's more efficient in terms of space (and probably power). So then I ordered this kit and the filter module for CW (wide/narrow). Wow -- I'm really impressed! Plug it in, tune around with it set to "Wide" and then switch over to "Narrow" and the signal is super-clear. Makes it really easy to pull things out of the noise and/or other stations. This makes the FT-817 (or any other filterless radio) very useable on CW. The kit is a pretty easy build if you've ever built kits before, and I'm quite certain a total beginner could do it, too, if they've ever done soldering. Thanks Richard! Rex KE6MT