VHF Ham Radio and the ST1300...

[k2mpw]

I'm asking anyone who is a ham and plays VHF radio while riding what antenna mount and antenna are you using? I'm asking because I can't seem to get an antenna to work well on receive! I've used a Yaesu VX7R and a Cheapo UV5R with the same exact results. The latest antenna on my ST is a Diamond NR770NMO. VSWR is less than 1.5:1 on both bands. Transmit works fine with a Sena SR10 bluetooth headset. 70cm is better than 2m but still suffers. There are a few experiments I need to do in order to investigate to see if the ST is as big of a noise source as I'm suspecting it to be.
Thanks!

 

[CYYJ]

This discussion might be of interest to you, it contains a large number of photographs of ST 1300s that are operated by police departments and fitted with VHF radios:

Pictures of different ST police bikes?

You might also want to have a look at the police bike supplement in the back of the Service Manual and see if there are any electrical system differences embodied on police specification ST 1300s to reduce electrical noise.

Below is a picture of a VHF antenna mount used by the federal police in France on their BMW motorcycles. It is unique - not sure if that design is of interest to you.

Michael

Gendarmes in France

 

[k2mpw]

Well it certainly fixes the issue of a proper counterpoise! Thanks.

 

[Jay B RDH]

Greetings.. Im KB8VMO... was considering putting 2m/440 on my bike.... something I was also wondering... has anyone built a circuit that allows the radio/ht audio to override music being run into helmet speakers?

 

[k2mpw]

I use the Sena SMH10R headset with the SR10 Bluetooth interface. I don't bother trying to listen to music becuase the SMH10R speakers absolutely SUCK for music. Tweaking the EQ of the cell phone can make the music barely tolerable. The second issue for me is that I ride with my better half and use the intercom feature of the SMH10R. It doesn't allow music sharing AND the intercom at the same time. Kinda puts a fork in using the intercom. As for the priority of who's on top, I'm sure its in one of the owners manual. I just never got that far.
Radio performance of both bands is good for close in simplex or repeater access if you are WELL within the inner circle range of a VHF machine or a little further out on 70cm. That's with a non ground plane dependent Diamond NR770 1/2 wave VHF / 2 half waves on 70cm..... The first antenna was a
Larsen 2/70 NMO. I have found no difference in performance. The mounting bar is ground strapped to the bike frame..

 

[k2mpw]

Well it seems that I've been at this from the wrong end. The totally awesome F4 LEDs that light the way are without a doubt, causing broadband noise that is raising the noise floor. The cheap Chinese four way square lamps I have under the mirrors are SCREAMING with noise. My guess is that the headlights are causing 15% of my noise and the aux bulbs are the other 85%. The radio is secondary to seeing down the road so it's research time! Taking a Yaesu VX7R HT with a stubby antenna and tuned to 1000Khz AM tells me that I really need to reroute the coax feed away from those coils! The radio burst into a crackle dance 6 inches from the valve covers!

 

[spiderman302]

As you most likely know you will have to fight the fight on two fronts.
The leds use switching regulators, you could try filtering the dc lines with standard EMI filters.
Or (I would) just change out all the switching regulators with linear regulators, there would be more heat to dissipate but for you there would be no noise. LM350s set as a current source,one for each light. just measure each lights current to determine the shunt value for current set.

The other problem is the spark plugs are spark gap transmitters. you could add emi filters around the ignition module low voltage DC side but this might not do much.
I always use DCI 146 broad band pass filters on 2 meters & 450, and Dunstar band pass filters on HF. Most modern receivers are wide open, no filtering, so any out of band energy will cause de-sense. There is even a good high pass filter that you could cascade with the band pass filters (ICE 400X).

I use FM (commercial broadcast 88-108) notch filters on my scanners, which makes them work so much better......

Minicircuits and ICE has a bunch of filters, ICE 413 for 2 meters. There maybe other better options available today I will have to look around.

Make sure that your antenna is resonant at the frequency of operation (low swr)

 

[k2mpw]

The LED headlight noise is just barely perceivable, plus getting back in and under the faring isn't my idea of fun! Tweaking the regulators is limited to adding snap on chokes on the input and output sides. The cheap road lights can be switched off so that's an easy fix. I can add a DC noise filter to the power input of the HT pretty easily. Along with the filter I can pull the red black zip cable out and give it a nice twist before routing it back in the bike (away from the ignition coils).

Bouncing between 2 meters and 70cm makes it difficult to use any kind of narrow band filter. The DCI filter wouldn't be a tough fir anywhere on the ST. The Diamond NR770 VSWR is under 1.5 on both bands as it is so I'm good there.

I think the next big move may be to take a shot at installing the Yaesu FTM-10r radio under the passenger seat. That way it's as far away from the spark gaps as possible! Power and coax cables can be much shorter. The one bummer is that for weather proofing, the factory cable can't be removed from the control head and its way longer than I need. I'm more concerned with the ability to pop the control head off the bike than with weatherproofing so I'm taking a shot at using the "short" 6" control cable that's used to connect the head to the body if the two are mated together. It terminates in a RJ45 male. I have a shielded cat5 6 foot extension cable to make the jump. The setup works on the bench but I have yet to test it on the ST. You can be sure that I'm looking to route the cable up the middle away from the ignition coils!

Thanks,
Michael

 

[spiderman302]

All the noise energy is down at base band (below 10 Mhz) so just using the DC noise filters may be enough. since you are only using vhf and uhf, a high pass filter would work on the antenna. FM is more noise immune than SSB, so what you are doing will help.

I use to run 40 meters mobile SSB in my jeep when I went exploring out in the Panamint and Death valleys using a TS-120 and a Hustler antenna a few decades ago, when repeaters were few. I contacted a Ham who was my neighbor to let my family know that I made it back to camp safely.

I have a CB fire stick on my ST1300 with the intent of making a 40m loading coil inline so that i can mount my IC-706mkIIg and get back on 40m mobile. I loved 40m since our SoCal mountains will not block the signal. I will have to put the Sena SR-10 on my need to have list..... let us know how well your noise abatement works.

 

[k2mpw]

I just did some surfing for any available high pass 50 ohm filter and came up with squat. It looks like a high pass filter will have to be home brewed. Aside from the HPF it looks like chokes, twisting the power cable, using a DC ignition noise filter and re-routing the cables are the first line of attack. The noise filter has been ordered from a Greedbay vendor and the search for the many snap on chokes that are in my collection has begun. I will try to post as much of the details as the "fun" occurs. Hopefully I can figure out a way to record the RX audio as the process goes along.

 

[spiderman302]

Since you not using HF you could use this for a high pass filter.

Diamond® Antenna ~ MX610 Duplexer

the common port goes to your dual band antenna, the vhf / uhf port goes to your radio and the hf port goes to a shielded 50 ohm dummy load.
It will give you 45 db of spur reduction which maybe more than enough.

 

[k2mpw]

It's scary when the manufacturer doesn't know the difference between a diplexer and a duplexer. I have a Comet branded diplexer somewhere but I think the band split is wider in that one port is HF up to VHF and the other is above VHF to UHF. Just my luck.
Thanks for the model info.

 

[spiderman302]

Yes, they have several versions, that is why I recommended that model. You are not running full duplex or multi-op so there is no need for a duplexer. The diplexer can be used for a filter since you are having low level interference. I have built a few repeaters and one is still in operation, solar powered at 2,870 feet elevation.
But do this as a last resort, if the other filters are not enough.

 

[AV8R]

My little UHF 1/2 wave antenna on my escort popo bike that I use at 470-520 MHz. (Simplex and half-duplex)
Antenna: Browning BR-178-S 380MHz 520MHz Pretuned 2.4dBd (unity gain if no gnd plane) Gain Land Mobile NMO


The low pass filter I used to eliminate alternator, LED switching noise that I could hear on the 2-way radios.

 

[k2mpw]

Thanks for the Pics! Love the air horn box on top of the radio!

 

[AV8R]

Not much room under the radio hood on the STP, so I stacked them.

Heres my 30w mobile and 5w portables I use on the escorts

 

[k2mpw]

Holy Two-Way Batman! Looks like you play peek a boo with the dash!
Can I guess that you use a half helmet so you can hear the portables?
Due to a full face helmet I had to use a mounted mic and speakers. I started off buying the Chinese crap from ebay and rewiring it to suit my needs but the squelch POP drove my nuts and the wires didn't help either. I found the Sena SR10 and thought it was the best idea ever....... until I used it. It works but it is far from perfect. Its pathetic to say but I actually pulled a tendon or something in my left hand while attempting to hit the PTT button on the handlebar at the same time I had to grab the clutch. STOOOPID move I know. It will not happen again ever cause my left paw is killing me now!
As soon as the DC filter I ordered appears I will be pulling the tupperware to install it and move the coax. I found the snap on chokes. I used two of them and got two passes of input power wire through them for the UV5R battery eliminator. I heat shrunk them in place. It's a waiting game now.

 

[AV8R]

No no no.

The 3 portables are not on the bike when I ride. Only the TK-8180 mobile radio that’s mounted between the bars. I have one portable on my belt for when im directing traffic off the bike and beyond BT range, either the TK-3180 or XPS-3000. The little TK-2180 without buttons and display is the “coach” radio I give to lead vehicle in a procession.

My helmets (full face modular and 3/4 open) have a Sena 20s BT comms kit with a boom mic and internal speakers. I use the Sena SR10-10 BT to 2-way radio adaptor to wireless link my helmet (and me) to the bike’s 30w TK-8180 mobile radio. Old-school motors use quick release wired connections between helmet and bike, but i know id forget and break things. So its wiress for me.

The bike has a wired Sena SR10-10 PTT button mounted on the left handle bar. Also have a wireless Sena PTT that keys the mobile radio as an option when off the bike but within BT range. This is clipped to my blouse near the left pocket.

The portable 5w (TK-3180 or XPS-3000) on my belt has a hanging mic which is clipped to my uniform blouse’s front lapel. The mic has an audio jack out port that has a cable that goes into the helmet 20s comms aux audio in jack port. This allows me to hear the portable within the helmet on or off the bike. I PTT and talk via the portable when off the bike.

Also have a Sena Prism Tube WiFi helmet mounted video cam. On the left handle grip is a Sena wireless remote control to the Sena 20s comms kit so I can control it without reaching up to the 20s jog-wheel on the helmet. Keeping both hands on the bars.

The iPhone is also connected to the Sena 20s via BT, which is where I get music, gps voice, and phone calls.

The 20s handles the audio traffic from the different sources. It mutes the IPhone and portable when the 2-way radio is tx or rx.

Im into tech, and “fly” combat fligjt simulations in an online virtual squadron (hence callsign AV8R) which has lots of monitors, data displays, HUD, radios, weapons systems, flying and combat. Im also an electrical engineer used to tech and data. So my eyes and brain are wired for multitasking. Still one has to scan data in the real world on a bike very fast and only as needed and when the environment permits. Else bad things can happen. I say this because monitoring displays and using radio while doing Escorting on a bike requires multitasking. Not for everyone

 

[k2mpw]

Ah, now I see said the goober with the injured paw. Sounds as if you put a lot of time into thinking it through. I do have a question. Do you recall the model number of the Sena BT remote PTT? I'm simply using the SR-10 interface with the wired PTT that comes with it. A BT option sounds interesting. I could remote my base radio into my living room with the BT PTT option.... (obviously not ST related......)
Thanks!

 

[AV8R]

Sena doesn’t have a wireless PTT, just a wired one. Sorry i was thinking of the BT PTT i used with the Pryme BT31 radio adaptor i just swapped out. Ill try to see if the Sena SR10 will pair with the Pryme PrymeBLU BT-PTT2 Wireless Bluetooth PTT Push-to-Talk device, but not likely.