Puzzling VHF problem.

[Saltytimes]

Hi there,
We are fitting out our 32 foot ketch for coastal cruising. Since doing a bit of work on the electrics the VHF has been playing up.

During the day the squelch on the VHF can't be controlled. It's all static, but still receiving and transmitting clearly. Once the sun goes down this problem is gone. The squelch controller works as normal. We have a handheld VHF that is working fine as well both night and day.

We have an antenna on the top of the mast, 12m high. I am sure the ionosphere has something to do with the clarity at night. But this is a new problem since disconnecting and then reconnecting the antenna from the back of the radio.

Any ideas on getting it working in the daytime again?
Thanks in advance ,

Jamie
Sv Charade
www.saltytimes.com

[GordMay]

Greetings and welcome aboard the CF, Saltytimes.

[transmitterdan]

Jamie,

Did you install or replace anything else on the mast? For example, anchor light or wind instruments or anything at all?

[ka4wja]

Jamie,
Yes, this seems like an odd problem, but since you haven't mentioned what radio, how old, when was it installed, what coax, what connectors, when they were installed, who installed then, what condition the radio and coax / coax connectors, etc. etc...
Nor, whether you did any other "electrics" work?? (such as any other devices that might be causing this interference.....any new lights, sensors, instruments, etc...)
I can only provide some general advice....

So, here are some helpful tips...


1) The ionosphere has nothing to do with this issue at all...


2) The very first thing to do is, to absolutely verify that the VHF radio is properly connected to the masthead antenna...
If the coax or coax connector is not making good contact, and/or is not properly seated/connected, there can be noise pick-up that could approximate this condition....
Since you mentioned this being a new problem, which is occurring since you've disconnected and reconnected the VHF radio's antenna cable, this is the first place to look...


3) One of the most likely causes of squelch problems such as this, is the radio itself....a faulty radio....sorry to say, but that's a fact...(although the fact that there is a specific time that this occurs, it is less likely here, than in most cases...)
Perhaps there was some old components that were nearing their end-of-life / falling outside of tolerance, etc. or circuit connections that were loose / corroded, etc. or wiring that was suspect, etc....
And, then as you moved things around ("Since doing a bit of work on the electrics"), there was enough change in the circuit to cause this problem...


4) Another highly probable cause, is a photo-sensor / light fixture nearby....whether a street light, patio light, etc. up to a 1/4 mile away, or something on your boat, or other boats close to you....(I have a local patio light that causes RFI on some HF freqs, right at dusk....it don't cause me much trouble, so I've not gone down the street and talked to the guy...but to have this cause troubles for you thru VHF, means that it would be an easy RFI source to find...)
This is especially a high probability if you also have a any VHF coax / coax connector issues....and even higher likelihood if you have an older radio...and even higher likelihood if you replaced / added other "electrics", such as lights, sensors, etc...


5) Although having a handheld VHF that does not have this problem would seem to highlight your primary VHF radio as THE problem....but that might not be an absolute, as the newer (?) handheld and its short antenna might not be being affected by any RFI source (photo-sensor light, etc.), that your primary VHF is being affected by...
And, you can try using your handheld as a "sniffer" to try to find the RFI source, but you'd need to start by connecting it to the masthead antenna and seeing if it is being affected or not...



I hope this helps...

Fair winds..

John

[Viking Sailor]

Since it is a daylight only problem on a radio, that is connect to the house battery bank, it is most likely the solar charger controller.

Cover the solar panels or disconnect the solar panels from the charger controller (check manual on how to disconnect,) and retest radio.

[Saltytimes]

Thanks so much for the responses. This is such a good lesson in how to post a solvable problem in a thread.

It's my first post and I most definitely didn't give enough information. But from the responses, the solar controller is newly installed and tomorrow morning we will test it by covering the panels.

It is an old VHF (an AWA 268) and we definitely need to consider the various troubleshooting ideas that John provided. We will work through them after testing the solar controller.
Again your responses are greatly appreciated.

Jamie

[ka4wja]

Jamie,
You're welcome!

BTW, I hadn't thought of a solar charge controller, as you didn't mention having solar, etc....but this is, of course, another possible cause (especially if combined with an old radio and suspect coax / connections)
And, if it's too windy to cover the panels, you can always just shut off the controller (I assume you have fuses/breakers on input/output of the controller)..


I'm not familiar with an AWA 268, but sounds like an old unit, not a modern Class D VHF-DSC radio, so if this is the case, I'd recommend spending a couple hundred dollars on a new VHF (a modern Class D VHF-DSC radio)....
Even if you find the trouble is NOT with your present radio, if it is not a VHF-DSC radio, I still recommend replacing it!


Also, you may want to tell us about your solar array, and especially what solar charge controller you have....as well as any other electrical systems / electronics on-board....as these will help everyone narrow down your problem...


I hope you get things sorted out..
Good luck and Fair winds..

John

[SkiprJohn]

Originally Posted by Viking Sailor

Since it is a daylight only problem on a radio, that is connect to the house battery bank, it is most likely the solar charger controller.

Cover the solar panels or disconnect the solar panels from the charger controller (check manual on how to disconnect,) and retest radio.

Darn, you beat me to it. I was just going to ask if there was a solar system aboard.

[senormechanico]

Our BlueSky 2512IX MPPT solar controller generates an open mic condition on VHF 16 for our handheld in the cockpit unless we turn the squelch all the way up.
The radio is kept on the wheel pedestal about 3 feet from the MPPT controller.
If I take the radio up to the bow, I can turn the squelch down to the first position up from "open squelch".
The radio with the masthead antenna is not affected.

[Saltytimes]

With Some testing this morning we have identified that it is our MPPT solar controller causing the static.

We tried a battery that is not connected to the solar system and we isolated the battery that is connected to the solar and the problem remained.

Then we disconnected the MPPT to the battery and the problem remained. Then we covered the solar panels and the voltage dropped from 18 to 13 volts at the input terminals and the static improved slightly. The further it dropped the more it improved.

We finally disconnected the solar input terminals and the radio performed as normal.

Overcoming this problem is my next question. Since it is an older Vhf, is replacing it the answer or will it happen with a new radio as well.

Any other suggestions for overcoming this?

Thanks,
Jamie

[SkiprJohn]

Sorry I can't help with a solution. It's good you found the problem.

[DeepFrz]

How close to the MPPT controller can you put your handheld and have it still work? That may answer your question. What make model is your MPPT controller. If it is some really cheap brand you may have to replace it. However, as John has said a number of times you probably should replace your radio regardless. Without knowing your system and where different items are physically placed, how antenna and power wiring are run etc. its pretty hard to troubleshoot it any finer than this.

However, check all cct. connections between the controller and your batteries and between your radio and the batteries. You could also try ferrite cores on the radio power leads. Also check all suggestions from John above. Did John mention buying or borrowing an SWR meter to check your coax to the antenna and your antenna?

[senormechanico]

It's always best to kill then noise at the source, rather than try to noise proof other devices at a distance.
Imho, ferrite beads or other shielding at the controller ought to be the first thing to try.

[hellosailor]

Also contact the MPPT controller manufacturer. Many companies are aware that their equipment creates unacceptable RFI under some circumstances, and some have retrofit or upgrade kits and other solutions that will solve the problem.


If it is still new, check your warranty as well.

[ka4wja]

Jamie,
I'm glad you found the cause of the problem easily...and yes, there may be some upgrades to the MPPT controller that can help, as well as shielding the controller and filtering right at the controller (both the input and output wires)...

If all else fails, look into a new controller...

{FYI, I have two Blue Sky 2512ix controllers, linked-together, and they cause NO RFI to VHF at all....and only a very small amount on a few odd places on HF, and have never caused a problem....they are mounted within inches of both my Icom M-602 VHF and Icom M-802 HF...}

But, also please check/verify you VHF antenna coax and connections....as these do have issues with age....
Actually, if your radio is as old as I suspect (a non-DSC-VHF), I recommend replacing the coax, antenna, and VHF radio itself...

VHF-DSC radios are inexpensive, as is good coax, and a new antenna....and considering that your VHF is your primary means of communication on-board (to other vessels and shore stations), especially for safety/emergency comms, it makes sense to keep it up-to-date, and in top shape!



Fair winds..

John