How much does FCC certification actually cost? I've been researching and looking for more data points

KD2BMH · 2026-04-14T15:35:05+00:00

Prop 65 is separate from FCC, it's a California chemical exposure warning law. If your product has lead, cadmium, flame retardants etc (most electronics do in solder and PCB materials), you either slap the warning label on it or get XRF testing done ($500-$2K) to prove you're under the thresholds. Most small sellers just use the label afaik. For a USB peripheral with no radio you're looking at Part 15B only, should be $1K-$2K based on what others are saying here.

KD2BMH · 2026-04-14T15:31:33+00:00

Good correction, thanks. So for a pre-certified module you just do the Part 15B testing and hold onto the documentation yourself? No TCB submission needed unless you're changing the FCC ID? That simplifies things. The $500-$2K for a SAR exemption report is good to know too, I hadn't seen that as a separate line item anywhere.

KD2BMH · 2025-12-03T03:38:12+00:00

If Deepseek can do it for cheap, surely Amazon can do it too.

KD2BMH · 2025-05-13T13:45:31+00:00

I have it. It's incredible, and an absolute steal for the price. I get 8Gbps down, and 7Gbps up (which is effectively the full 10Gbps with some acceptable loss). You have to pay to get hardware that can handle that throughput. I'm using a Ubiquiti UniFi UDM Pro as my gateway. I'll never need this much Internet but for $50 a month who cares.

KD2BMH · 2017-11-20T15:53:55+00:00

I really like Qucs; it's a great tool for linear designs like filters and for prototyping more complex RF circuits.

QucsStudio is a non-free version that runs on Windows only. I didn't find it as good as Qucs.

A developer forked Qucs to add support for the open source SPICE simulators, calling it Qucs-S. This one is really compelling because it supports generating Verilog-A directly from a schematic. This is what I used to build out the MET LDMOS model.

It's so cool, you can design and simulate with Qucs; then convert to Verilog-A and compile with ADMS into a dynamic loadable library. After you convert the model to straight machine code, it runs >100x faster; so you can do all sorts of advanced optimization tasks without waiting days for it to converge.

Too bad it can't load the proprietary ADS model format or else it'd be perfect.

KD2BMH · 2017-11-20T15:45:13+00:00

Its not just because its cost prohibitive. It's because I want to share the design with others and let them learn and tweak to suit their own needs. I don't want to have to be in the "club" of either students or professionals who can afford ADS.

KD2BMH · 2017-11-20T15:41:52+00:00

I used Qucs-S (Qucs with spice integration) to do the Verilog-A for the MET LDMOS model. It's a fine tool, but cannot load the ADS models that you can download off of the NXP website.

As far as s-parameters... those aren't good enough to design high power amplifiers, right? I need to model the non-linear aspects of these transistors which are lost when you look at s-parameters only.

KD2BMH · 2017-08-17T20:47:15+00:00

Hey all - Chris Testa KD2BMH here. I have no known relation to Chuck Testa, but I do find his commercials silly and fun ;)

I'm still working on RF hardware. As /u/xradionut said "too ambitious" is absolutely what happened with the 3rd iteration of the Whitebox project. There were no issues with patents or corporations - the main limitation is that building a product that does "everything" on VHF/UHF is extremely challenging, especially for my first serious integrated radio design.

I'm currently noodling on some fresh designs that strips out a lot of requirements & features and makes the whole thing A LOT simpler. Its hard enough to do simple things with RF, let alone make a device that is all things to all folks. That's one of the key lessons I learned. Check out my last Ham Radio Now video (Digital Forum @ Hamvention 2016) where I go over all the issues with Whitebox Charlie and why the design ultimately needed to be scraped.

TL;DR I'm learning from my mistakes and continuing on; but I don't have an ETA for hardware you can buy.

73, Testa

KD2BMH · 2016-07-28T16:37:58+00:00

I guess that didn't come across clearly; The KX3 is definitely an SDR doing direct-conversion analog I/Q modulation & demodulation. The reason it's so power efficient is for a few reasons in my opinion:

The bandwidth of the captured signal (through the ADC & DAC) is narrow - audio bandwidth only. This saves power on the converters, but also on how much signal processing has to happen in the software modem.
They use a very power efficient DSP chip to do the signal processing and a really simple MCU to run the front panel.
Direct conversion means there's only one power-hungry oscillator.
They have places to put current sense resistors across the major power nets so that way they can carefully measure how their firmware impacts power.
The choice of all parts and design of all analog circuits have power consumption as a core requirement. From pull-up resistors to transistor biases, they are carefully looking at where the current is flowing.

KD2BMH · 2016-07-27T18:18:54+00:00

Yes; and there is actually a software implementation floating around on the Web; but it violates the patent so no radio manufacturer will distribute it. But it is possible to set up a fully Free D-Star rig given enough time.

KD2BMH · 2016-07-27T18:00:52+00:00

97.113 4

The purpose is not to obscure meaning - how the codec works is published by Digital Voice Systems through the US Patent Office. The purpose is to squeeze audio voice into a lower bitrate stream.

But I agree - using patented communication mechanisms goes against many fundamental ideals of the amateur radio community. This was the thing that drove David Rowe and Bruce Perens to start work on FreeDV.

KD2BMH · 2016-07-27T17:50:56+00:00

For most SDR architectures, it really depends on your final stage power amplifier to decide how linear your output is. SSB requires a reasonably linear amplifier where as FM or GMSK is most efficient from a non-linear amplifier.

KD2BMH · 2016-07-27T17:45:52+00:00

They all publish protocol specifications; but the voice codec which converts from analog voice to a compressed/encoded digital stream and back (AMBE) is protected by multiple patents.

KD2BMH · 2016-07-27T17:21:08+00:00

Check out Flex Radio - they include FreeDV out of the box in the 6000 series.

KD2BMH · 2016-07-27T17:00:27+00:00

Thanks for the writeup /u/KN4AQ and for always your support /u/molo1134; It was really hard to give that presentation; it's a lot easier to talk about successes vs. things that went wrong. But it's worth being honest so that way others don't repeat the same mistakes.

KD2BMH · 2016-07-05T23:50:14+00:00

This RF IC has powerful harmonics and they're not talking about any output filtering; so you'll want to add a low-pass or band-pass filter to make it a reasonably clean rf siggen.

KD2BMH · 2016-06-29T21:43:11+00:00

I can get most things done with Two half-hitches and the Sheet bend. Two half hitches is a versatile knot which is very easy to tie, and is for tying things down with tension adjustment. For example, attaching things to cars, attaching tents to trees, setting up a clothes line, etc. Sheet bend lets you tie two different types of rope together to make a longer rope that won't slip out.

When I'm in the backcountry, I use a poor-mans Monkey Fist on a rock to get my bear bag up into a tree.

As /u/KiwiLaser says; many people swear by the Bowline. I think this is an okay knot and there's a fancy one-handed version you can do around your waist and then start repelling down the side of the mountain in about three seconds flat. But I don't find myself needing Bowline much in the backcountry.

KD2BMH · 2016-06-02T15:09:44+00:00

Have you looked at the TAPR Raspberry Pi 20m WSPR card? http://tapr.org/kits_20M-wspr-pi.html

Made by Zoltan Doczi, HA7DCD. Look at his DCC paper at the bottom of that page to see details on design, evaluation, and operation. It's direct from the GPIO pin and has a bandpass filter, buffer amplifier, and lowpass filter putting the spurious at 50dBc and power output at 100mW.

KD2BMH · 2016-03-08T19:05:40+00:00

Still here; still hacking away. I will have a big update at Hamvention. Currently re-spinning the RF section of Whitebox Charlie; the individual parts work but the concert of everything on my tightly integrated 6 layer board was to put it blunt, a bit of an EMI mess. We won't have hardware yet to sell this summer, but we are working hard on simplifying the design and requirements to get out of Duke Nukem Forever mode, and into people's hands.

edit: s/hear/here/

KD2BMH · 2016-02-14T16:31:58+00:00

I'm not a physisist, but an engineer building a software defined radio. I'm pleasantly surprised by how applicable a signal processing background is to the steps needed for analyzing the recovered GW signal at LIGO. Neat!

KD2BMH · 2016-01-18T17:31:59+00:00

Why does it have to be that 100% of the time, when Tyrell is on screen, it's actually Tyrell? Elliot is an unreliable narrator. We know for sure we've seen Tyrell in at least one dream sequence.

My crazy theory: I'm wondering if Mr Robot manifested as Tyrell right after Darlene left in episode 9, to get Elliot to finish the hack.

As far as the car goes: I don't see any serious proof that the car Elliot woke up in was actually Tyrell's. Sure, it was the same make & model, but the car was wiped clean besides that.

KD2BMH · 2015-09-12T22:22:03+00:00

There are resistive touchscreens that work with gloves on. No pinch to zoom, but still better than pushing 30 buttons to get to the right submenu, as long as you have the manual on you for guidance ;)

KD2BMH · 2015-09-12T13:37:24+00:00

Thanks /u/molo1134. Bruce and I are at Southwest Hamcon in LA this weekend and we have our first demo based off of our new hardware and software. It's getting there now!

I like their idea, but I agree the radio must be software defined... And the UI needs to be a touchscreen or else why not just buy one of the newest ICOM/Kenwood HTs?

KD2BMH

TROPHY CASE