Radar overlay with PG500

[Anonymous]

Hello,
I have a Navnet VX2 1834 with C-Map. I purchased a used PG500 so I can get radar overlay.
It is mounted midship at about the waterline. I cleared memory and then did a calibration. However after 5 or 6 circles it would still not calibrate. It was mounted on a small piece of aluminum so I moved it about 2 feet forward so that is not near any metal.
After moving it I was able to calibrate after 3 circles. I now have Auto and Status LED lit.
However my overlay seems to be 15 to 20 degrees off and is worse going south compared to north. Are there any other adjustments I need to make? I tried re-calibrating with about the same results. I have attached a picture of the overlay to show the offset.
Also can you tell me what the faint green line is to the left of my track is?
Thanks!

 

[Johnny Electron]

Also can you tell me what the faint green line is to the left of my track is?

The red line is your course vector line and the green line is your heading line.

Please ensure you are not using a flux gate compass on a metal boat.
For radar overlay to line up correctly there are many setup items that must be correct.
- Ensure your radar antenna type setting is correct for the radar you have connected.
- Ensure that the radar (video) heading alignment has been done with the bow of the boat. (radar image correctly aligned to bow when in heads up)
- Ensure that heading (Mag or True) setting under radar setup matches the type of heading you are feeding the display.
- Ensure that the unit is in live mode for RADAR, SOUNDER, and PLOTTER.
- Ensure heading data numbers displayed at the top of the radar screen are correct. (normally matching your COG and steering compass when moving in calm waters)

 

[Anonymous]

Hi Johnny, Thank you for the reply.
The boat is fiberglass and there is no metal within close proximity to the compass.

I will check and adjust all the settings you have mentioned.

 

[Anonymous]

Hi Johnny,
I did all the steps that you outlined above. All the settings were correct except for the heading setting. The VX2 was set for Magnetic and the PG500 was outputting True. I have change it so both are True. However I am still off by 20 degrees or so. My Radar stand alone alignment Is perfect as is my stand alone charting, However when combined they are off.
I looked at correcting this by my radar heading adjustment but wont that make my stand alone radar incorrect?
Any suggestions are appreciated!

 

[Johnny Electron]

So your compass has a solid or flashing TRUE light?

 

[Anonymous]

I will be back on the boat this weekend and will check.
Is there anything else I should look for?
Do you suggest both units to be set for true or magnetic?

 

[Anonymous]

Hi Johnny,

You were right! The Auto and Status light are lit solid so the PG500 is in magnetic mode.
I change my VX2 to Magnetic and everything seems to line up.
Thanks for the help!

Dave

 

[Johnny Electron]

Glad to hear it. :jump