Noisy Signal?

[bob95065]

How do I fix a noisy signal? The post below said to add a resistor. Can someone show me a picture or diagram of how to do this wuth resistance values? This caused me to think I can fix my Airtronics RD6000 issues.

Bob




We will have to separate the different issues.
To make sure your cable is OK:
connect it to both Tx and computer.
Do NOT start FMS or SPP
Select the right input using programme sndvol32.exe -r
Start Winscope as indicated in the Step-by-step section of my site (www.SmartPropoPlus.com)
If you see nothing or random noise then your hardware (Cable, Tx, sound card) is not good.
If you see a noisy signal then you might need to lower the input volume or add a resistor.
If the signal is good then continue.

Start FMS:
This will also start SPP
Does the the signal disappear from Winscope?
If so, SPP has changed the audio source selection. Click on the SPP icon in the system tray to select the right source. Make sure that the signal is on the Winscope now.

Select the correct modulation type
I'm not sure what it would be for your model. I think it has some proprietary PCM that is not supported by SPP. You will have to move to PPM for simulation. Do that on both SPPconsole and Tx.

Calibrate FMS

Hope this helps

[shaul_eiz]

One of SPP users supplied my with this schematics:

Let me explain:
The black line going to the RC is the signal line connected to your transmitter. The blue line is the ground.
The two resistors are merely a suggestion, you can use many other values as long as you adhere to the following rules:
1. The large resistor should not be in the range of 5-50 Kilo-Ohms.
2. The small resistor should be in the range of 1/3-1/20 of the large resistor.
Examples are:
10KOhm/1KOhm, 22KOhm/4.7KOhm, 47KOhm/3.3KOhm etc.
I'll be interested to learn which values you found to be best.

[bob95065]

Are you sure the black line is the signal? It looks to me that the tip of the plug in the drawing is blue and so is the line to the transmitter. The tip is usually the signal and the barrel is ground, no?

[shaul_eiz]

You are probably right. However, SPP does not care.