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[W1JPP]

I recently purchased an earthquake IG800W generator. (800 watts peak). Its supposed to be a pure sine wave output.

The good news is i tested it with my old ts-520S into a dummy load, and it handles the 100 watts (all I will be running) with no issues. I assumed it would.

The bad news is when I hooked my rig up to my antenna to test out with a QSO, I noticeable hash/static...of approx S5-S6 on all bands and more on 160m

I suppose good news: When I left the generator running just outside my shack, which is relatively close to my antennas) but not used to power the rig, (I used house power), I had no noise at all...so the noise must be coming from the electric power out of the generator vs the motor/generator itself.

Any suggestions as to the best way to filter the power out of the generator, if thats an option.

I only paid $100 for it, and never used, and the purpose was for charging a battery, so if it wont work, no big deal...but if I can filter the power out for transceiver use, I'd like to have it as an emergency option.

I did find this youtube video - which seems to work if I want to build something - just didnt know if there are alternative solutions

https://youtu.be/ECogK3pCp28



Thank you.

[NA6O]

See p. 23 of http://www.k9yc.com/RFI-Ham.pdf

A substantial common-mode choke, per the design described in Jim’s document, and possibly a commercial EMI filter (SAFELY enclosed and properly wired), are required. The alternative is to sell the beast and get a Honda 2000i, which is known to be RFI-free in almost all cases.

Gary NA6O

[AI5BC]

I recently purchased an earthquake IG800W generator. (800 watts peak). Its supposed to be a pure sine wave output.

Well guess what? It is not Pure Sine Wave. If it were, you would not have the problem. What you have is a generator/inverter and now you are stuck having to use a ham Band-Aid to try to fix your mistake. Unfortunately, you will never eliminate the noise, you might be able to make it usable, but never eliminate it.

What you can try to do is make a common-mode noise filter using FT400-31 doughnut ring with as many ugly turns as possible with the AC line cord. Good luck.

[VE3HIX]

From your tests, it seems that you have inverter hash noise, not ignition noise. If your generator does not have a built-in hash filter, there are plenty of instructions on the internet showing how to build an external filter. Try attaching a ground rod through a short wire to the generator frame to see if that makes a difference.

In my own experience, a grounded, shielded AC cord makes the most difference for ignition noise when there is little hash noise (but a shielded AC cord is hard to find).

Please keep us informed.

Cheers,
Bob VE3HIX

[AI5BC]

Try attaching a ground rod through a short wire to the generator frame to see if that makes a difference.

Cheers,
Bob VE3HIX

Complete waste of time.

[K8AXW]

Complete waste of time.

Wasn't it Edison who responded to a similar "waste of time" comment about his 96 failed attempts to create an electric light bulb..."not a waste of time.  I learned there are 96 things that doesn't work!"  (Paraphrased)

Almost everything we do has been done before...many times. 

Unfortunately, the filter solution will cost almost as much as you have invested in the lil generator.

Also, unfortunately, BC is correct.

While Honda makes a fantastic generator, they also command top dollar.

You can look at a filter build as a fun project that you might use for years. 

[AI5BC]

Complete waste of time.

Wasn't it Edison who responded to a similar "waste of time" comment

It is a complete waste of time. Simple physics, dirt is NOT THE SOUCE of the noise energy being generated. The generator is the SOURCE of the energy entering the radio in Common-Mode on the line conductors. In any power good power line filter, the first component is a capacitor across the output (L-N or +-) to short out high frequencies and send the noise energy directly back to the source where it came from. The capacitor stage is followed by a common-mode choke stage to block (high impedance) any noise let through from the first stage capacitor. Finally, the third stage is another capacitor across the line for good measure before feeding the load device with power. No ground involved, ground is only there for safety to make the breakers operate and keep touch potential to acceptable limits. 

[VR2AX]

When I left the generator running just outside my shack, which is relatively close to my antennas) but not used to power the rig, (I used house power), I had no noise at all...so the noise must be coming from the electric power out of the generator vs the motor/generator itself.

Isolate the generator from the RX system (only use to power TX/amp) - separate RX on battery or (maybe) RX on house mains but generator not connected to house mains/earth (safety issues?)

[AI5BC]

Isolate the generator from the RX system (only use to power TX/amp) - separate RX on battery or (maybe) RX on house mains but generator not connected to house mains/earth (safety issues?)

Big time safety issues if it were possible. To use a generator in your house comes with all sorts of code requirements. Done properly, when you connect the generator to the transfer switch, the green wire in the generator ambilocal cord (AC Equipment Ground) is connected to the house ground system. If there were a fault on one of the homes branch circuits, the ground wire provides the fault path back to the generator to operate the generator circuit breaker and clear the fault.

For portable operation, everything is Plug-N-Cord connected to the generator. Each cord plugged in has an AC Equipment Ground Wire so if there is a fault in the equipment, it has a ground wire to return the fault to the generator. No earth connection is required or needed. You are not connected to the utility and have no risk of being exposed to utility high voltages which would require you to have an earth ground to protect you from. Same for lightning, little to no chance of being a problem for a temporary portable generator. 

So here is the problem, the OP situation does not fit either application above. If you placed one piece of equipment using house wiring for power, and then power another piece with a separately derived system like a generator isolated from the house ground system is extremely dangerous. If there were a fault in either system, the voltage difference between the chassis of the TX and RX will be 120 VAC waiting for you to find when you touch them and light you up.

Anyway ground has nothing to do with the OP's question and driving a rod in the dirt is pointless.

[VR2AX]

Great information. Daughter and son in law acquired a 20kw generator, I have so far ducked getting involved...

Point was more from his quote, the interference does not seem to be airborne (ether per Einstein photons per Weinsberg or whoever). So the genny is not radiating.

[W1JPP]

Update

So after reading thru these answers / suggestions and being impatient.

I had a couple spare size 240 type 31 toroids. So I took a power cord, cut the female side and wound probably 15 turns on each and put them close to each other and probably 12” from where the male plugs into the generator

Added a female receptacle to the end I cut off. So basically a 10’ extension cord with the toroids right by where I plug into the generator.

First without the generator running I checked my noise floor on a few bands.

Then with the generator running and powering my kenwood t’s-520s, I checked the noise on the bands I checked before.

Good news. Noise floor was the same. For me, this time of day - 3:30 eastern (730 usc) …75m is around s6. 40m around s3 and 20m around s1.

With the generator powering my rig the readings were all the same whether powering off house power and no generator running or powering off the generator.

So for me, this solution seemed to work.

[W9IQ]

Nice work. Common mode chokes such as you installed tend to be the more reliable, repeatable solution.

- Glenn W9IQ

[W1JPP]

Nice work. Common mode chokes such as you installed tend to be the more reliable, repeatable solution.

- Glenn W9IQ

Thank you Glenn. I’m Pleased with the solution and outcome.

As a side, I want to thank you for all your contributions here. I have personally benefitted from and number of your suggestions and guidance. I appreciate it.

Joe
W1JPP

[W9IQ]

Nice work. Common mode chokes such as you installed tend to be the more reliable, repeatable solution.

- Glenn W9IQ

Thank you Glenn. I’m Pleased with the solution and outcome.

As a side, I want to thank you for all your contributions here. I have personally benefitted from and number of your suggestions and guidance. I appreciate it.

Joe
W1JPP

Thank you, Joe - you are kind to say so.

- Glenn W9IQ

[KH6AQ]

Just this last weekend I fired up a brand new non-inverter 4 kW generator for a portable 160 meter operation. Initially it produced S6 noise (3 kHz BW) on a 1/4 wavelength groundplane. Using items on hand we wrapped the line and neutral 10 times through two stacked F240-31 ferrite cores to form a CM choke. That knocked the noise down to S4. We then had three earth grounding options:

No earth ground
Earth ground to generator GND stud
Earth ground to the extension cord ground wire (CM choke output side)

The generator ground knocked it down just a bit and the extension cord ground knocked it down to S3 which was acceptable. Ideally -- and what we will do for another topband portable operation this month -- is to wrap line/neutral/gnd through the cores and connect the output side ground of the CM choke to earth ground. We will also have the option of 0.01 uF Y-capacitors connected from line and neutral to ground on the CM choke output side.