Search found 708 matches

by Daniel Wee
Sat 07 Mar 07 2009 8:17 pm
Forum: Projects
Topic: DragonPro
Replies: 20
Views: 17712

DragonPro

The prototype board appears to be working now, even with the misaligned pins. We are starting off with the XT at 8.0MHz and then activating a 10-times PLL to kick the clock up to 80MHz, giving us the instruction clock (Fcy) or 40MIPS. This is twice as fast as what the DragonOSD is running at (20MIPS...
by Daniel Wee
Fri 27 Feb 27 2009 8:58 pm
Forum: Projects
Topic: JR9XII / 9303 modular connector
Replies: 1
Views: 3540

Internal view of rear PCB

The following are some shots of the rear PCB.
IMG_0931.JPG
Rear of modular connector
IMG_0931.JPG (86.11 KiB) Viewed 3595 times
IMG_0928a.JPG
Rear of D.S.C. connector
IMG_0928a.JPG (86.28 KiB) Viewed 3595 times
Daniel
by Daniel Wee
Fri 27 Feb 27 2009 8:52 pm
Forum: Projects
Topic: JR9XII / 9303 modular connector
Replies: 1
Views: 3540

JR9XII / 9303 modular connector

The JR modules uses a 5-pin connector for their transmitting modules. These carry power and the PPM/PCM signal that the module needs to send out the RF signal, and returns it to the antenna. IMG_0942a.JPG IMG_0939a.JPG The pin-assignments for the connector are as follows:- IMG_0943a.JPG The PPM sign...
by Daniel Wee
Thu 26 Feb 26 2009 5:40 pm
Forum: Projects
Topic: 2.4GHz Diversity Video Receiver
Replies: 4
Views: 6678

Re: 2.4GHz Diversity Video Receiver

The board currently works but preliminary tests suggests that it might be good to shield the detection circuit as it is very sensitive to changes. Future board layouts should be more symmetrical in terms of trace lengths for the signal paths. The linear regulator is getting pretty hot so we should p...
by Daniel Wee
Thu 26 Feb 26 2009 5:36 pm
Forum: Projects
Topic: 2.4GHz Diversity Video Receiver
Replies: 4
Views: 6678

2.4GHz Diversity Video Receiver

Most video diversity units out there rely on sync-detection or RSSI in order to determine the best antenna/receiver choice. Both these systems are weak though, with the RSSI method being marginally better than the sync-detection method. This project uses a novel method of assessing the best signal. ...
by Daniel Wee
Thu 26 Feb 26 2009 10:54 am
Forum: Projects
Topic: PPM data streams
Replies: 3
Views: 7696

Multiplex Royal evo9 PPM data stream

The following trace is from the Multiplex Royal evo9. The first thing you notice is the large voltage swing - up to 8V relative to ground (0V). This could pose issues to inputs expecting TTL compliant levels or inputs that are not tolerant to the higher voltages. In this trace, the vertical recticle...
by Daniel Wee
Thu 26 Feb 26 2009 10:30 am
Forum: Projects
Topic: PPM data streams
Replies: 3
Views: 7696

PPM data streams

The attached file is the scope trace of the PPM data stream from the JR9XII (equivalent to the JR9303). The trace is taken relative to the shield line from the D.S.C. port behind the radio. The vertical recticle is 500mV, and the horizontal recticle is 2.0ms. JR9XII_PPM.jpg You will notice that the ...
by Daniel Wee
Wed 25 Feb 25 2009 9:00 pm
Forum: Projects
Topic: UHF R/C control Link - Thomas's hardware design
Replies: 1
Views: 5251

UHF R/C control Link - Thomas's hardware design

This thread is to journal the developments made with this collaborative project with Thomas Scherrer (OZ2CPU).