Michel Spelier wins the world again on 160 meters
Michel Spelier, ON7EH, operating as OP3T, has done it again: another world-winning result on topband. In the 2026 CQ 160 CW contest, he finished #1 in Belgium, #1 in Europe, and #1 worldwide in the Single Operator Low Power Non-assisted category.
That alone is impressive. But the real RF story is what sits behind the certificate. Michel did not simply repeat last year’s setup and hope for the best. He kept refining his station, measuring, comparing, rethinking weak points, and making targeted changes to the receive chain until it behaved the way a serious 160-meter contest station should.
This is also what makes the story especially interesting for us: Michel was not just using a finished off-the-shelf product. He was already testing the RF.Guru limiter while it was still in the test phase, before it had officially gone live as a product. That meant the field feedback was immediate, practical, and brutally honest, exactly the kind of feedback that helps a design mature properly.
A topband station that kept evolving
Michel has been pushing hard on 160 meters for years. Beverage systems, switching, common-mode control, corrosion problems in field hardware, receive protection, attenuation strategy, and filter experiments were all part of the journey. Even after finishing 4th in 2021, taking 1st in 2024, and then landing 2nd in 2025, he kept improving the installation instead of treating it as finished.
That mindset matters enormously on topband. Weak DX and multipliers are often decided at the margin. A receive chain that is only slightly quieter, slightly calmer, or slightly more linear can make the difference between copying a needed call correctly and losing it in the mud.
Michel also insisted on something we strongly agree with: if a technical limitation or side effect shows up in a product or a station chain, it should never be glossed over. It should be measured, challenged, reproduced, and documented. In this case, everything we pinpointed in the field was re-tested at the RF.Guru lab, confirmed again with measurements, and eventually folded back into the product specifications and datasheet. That is exactly how RF hardware should evolve.
The setup behind the 2026 result
For this winning result, Michel confirmed that the RF.Guru HF RX Frontend Protector - Galvanic Isolator & RF Limiter and a homebrew high-pass filter were both in line during the contest.
The important nuance is that this was never a one-box story. Michel’s receive chain was the result of continued work on Beverages, switching, chokes, attenuation, receiver-side decoupling, and front-end behavior. The limiter/decoupler was one part of a larger, carefully evolved system, and Michel was one of the operators helping validate that design while it was still being refined.
In Michel’s case, three elements reinforced each other: receiver protection against overload, galvanic decoupling at the receiver side, and targeted filtering to remove strong unwanted energy before it could push the chain nonlinear. The result was not “magic gain.” It was a calmer, cleaner, more predictable receive path on 160 meters.
The issue we hit: strong off-band energy drove the chain into IMD
During testing, Michel noticed something important. On one of his quieter Beverage directions, inserting the limiter appeared to raise the visible noise floor. Without the limiter, he saw an extremely low baseline. With it in line, the displayed noise rose and the trace looked visibly more “rippled.”
That was a red flag, and Michel was absolutely right to call it out. We then worked through the problem step by step. The conclusion was not that the limiter was somehow “making noise” by itself. The real problem was that very strong signals below the 160-meter band were pushing part of the receive chain into nonlinear behavior, which then showed up as intermodulation and apparent noise-floor pumping.
Michel’s own measurements made that very clear. A small attenuator change was causing a much bigger change in the displayed noise than it should in a linear system. That is classic overload behavior.
The breakthrough came when Michel inserted his homebrew 1.5 MHz high-pass filter ahead of the critical part of the receive path. Once that HPF was in line, the chain returned to normal behavior. A 2 dB attenuator change again produced roughly a 2 dB noise change. In other words: the system was linear again.
Before the HPF, Michel’s analyzer plots showed a dense carpet of strong LF/MF/MW energy below 1.8 MHz. After the HPF, that broad unwanted energy was dramatically reduced. Many of the signals in the -50 to -60 dBm range were knocked down by roughly 55 to 60 dB, and the remaining strong carrier around 1458.75 kHz was reduced by about 22 dB. More importantly, the receive chain stopped behaving like an overloaded nonlinear system and returned to predictable, linear behavior.
Why a limiter, decoupler, and HPF can improve practical SNR
This is where the engineering matters.
The limiter protects the receiver and preserves usable headroom
A limiter does not improve SNR by adding gain. Its job is to keep harmful peaks, coupled RF, static events, or accidental transmit energy from slamming directly into the receiver input. In the real world, that can save front ends, reduce recovery problems, and keep the receive path more robust under contest conditions.
The decoupling stage helps block unwanted common-mode return paths
Receiver-side galvanic decoupling can reduce the amount of common-mode garbage that rides in from the outside antenna system toward the receiver. In some stations, especially with passive antennas and long outside feed paths, that can materially lower the noise floor. In Michel’s station, the pure noise-floor benefit from the decoupling stage alone was modest because his common-mode control was already quite good. But the isolation still mattered as part of the overall receive hygiene and protection strategy.
The HPF removes strong signals you do not want but that still consume dynamic range
This was the decisive point in Michel’s installation. Signals below 160 meters were not part of the wanted reception, yet they were still large enough to stress the chain. Once Michel filtered them out, the limiter and the rest of the receive system no longer had to deal with that extra burden. The result was a calmer, cleaner, more linear 160-meter receive path.
That is why filtering can improve practical SNR even when it adds a little insertion loss. A tiny loss is often a very good trade if it buys back front-end headroom and removes the mechanism that was creating intermodulation in the first place.
A collaboration that directly fed back into the product
We want to underline that part clearly. Michel kept testing, measuring, and reporting back. We kept discussing the likely mechanisms, the order of the chain, the role of common-mode behavior, the influence of strong off-band signals, and the most sensible next experiments.
That kind of back-and-forth matters. It is the difference between selling a part and actually learning something from a demanding real-world station. Michel’s result is his achievement. What we are proud of is that the RF.Guru limiter/decoupler was part of the chain, that Michel was testing it while it was still pre-release hardware, and that the collaboration helped sharpen both the product and the receive strategy around it.
So this is not a “one box won the contest” story. It is much better than that. It is a story about field testing, measurement discipline, lab confirmation, and design updates that were serious enough to end up reflected in the final product documentation.
What Michel may test next: can a low-pass filter improve it even more?
The next logical experiment is to test whether an additional low-pass filter, for example around 5 MHz, can improve the receive chain even further on 160 meters.
Why might that help? Because on 160 meters, energy well above the low HF region is still unwanted. Strong signals above 5 MHz can still consume dynamic range in an LNA, attenuator, limiter, or receiver front end. Even if you do not hear those signals on frequency, they can still contribute to mixing products, compression, or AGC misbehavior.
A suitable LPF may therefore buy back extra headroom by removing another block of off-band RF from the chain. The tradeoff is usually a small amount of insertion loss. Whether that trade is worthwhile depends entirely on the station environment. At some QTHs it will help. At others it may make little difference. That is why Michel wants to test it rather than assume the outcome in advance.
A high-pass filter solved Michel’s strong sub-band problem. A low-pass filter could, in a later step, reduce strong higher-frequency HF energy that still consumes front-end headroom. Used together, HPF + LPF form a tighter operating window for the actual band of interest. That does not guarantee a better result at every site, but on crowded RF locations it can be surprisingly effective.
The larger lesson from Michel’s 2026 win
Michel’s new world-winning result is impressive on its own. But what makes it especially valuable for us is the engineering lesson behind it.
On low bands, receive performance is rarely determined by one heroic component. It comes from the full chain: antenna behavior, switching layout, common-mode control, corrosion-resistant field hardware, smart attenuation, receiver protection, and filtering that matches the actual RF environment.
Michel kept pushing that chain forward. The RF.Guru limiter/decoupler played its part. The homebrew HPF solved a real overload mechanism. And the next round of refinement may still bring more.
That is how serious topband stations evolve. Test. Question. Measure. Improve. Repeat.
Congratulations, Michel
Congratulations to Michel Spelier, ON7EH / OP3T, on another outstanding 160-meter CW result and on proving once again that low-power success on topband is as much about listening quality as it is about transmitting ability.
We are proud that the RF.Guru limiter/decoupler was part of the chain, proud that Michel was already testing it before product release, and proud that the issues found in the field were serious enough to be re-tested, confirmed, and documented properly rather than ignored.
Mini-FAQ
- Does a limiter automatically improve SNR? No. A limiter mainly protects the receiver and helps keep the receive chain usable under overload conditions. If strong off-band signals are the real problem, filtering is often what restores linear behavior and improves practical readability.
- Why can galvanic decoupling help HF reception? Because it can interrupt unwanted common-mode return paths between the outside antenna system and the receiver input. In some stations that lowers the noise floor significantly. In others, the main benefit is cleaner receive-chain isolation and better receiver-side hygiene.
- Why did Michel’s HPF help so much? Because strong signals below the 160-meter band were pushing the receive chain into nonlinear behavior. Once those signals were filtered down, the chain behaved linearly again and 160-meter reception became much cleaner.
- Why test an LPF next time? Because signals well above 160 meters can still consume front-end headroom and create mixing products. A good low-pass filter can sometimes buy extra quietness and dynamic range by removing that unwanted energy before it reaches the sensitive parts of the receive chain.
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