NEWS from Andy

NEWS from Andy, G4JNT

Til: "Ukmicrowaves (ukmicrowaves@yahoogroups.com)" <ukmicrowaves@yahoogroups.com>
Fra: Talbot Andrew <actalbot@mail.dstl.gov.uk>

Dato: Mon, 19 Dec 2005 10:10:43 -0000

Emne: [ukmicrowaves] DDS Sources for beacons

Just uploaded a couple of files to www.scrbg.org/g4jnt There is a complete hardware description of the new AD9852 based driver for GB3VHF (which should be coming on stream around the middle of January transmittting in JT65 and CW). Also a file containing several utility programmes for use with DDS chips and frequency sources. File DDSBeacons.zip :

Two progs for calculating the frequency values for AD9850/51/52 DDS chips when used as beacon sources generating WSJT data modes and RTTY, as well as the carrier / CW frequency.

DDSBCN.EXE generates the codes needed for the case of the DDS directly generating the output RF, possibly via a frequency multiplier.

REVDDS.EXE is used when the DDS forms part of a PLL, see the descriptions for the GB3SCX and GB3SCF microwave beacons on www.scrbg.org . In this case the DDS generates the reference frequency while being clocked from the VCXO. The two progs will need the VB run library to function - download UWBCNMON.ZIP to install this if you don't already have it.

Also a couple of other utilities needed for programming a JT65 message the VHF Beacon Driver module. .EXEs but this time 16 bit DOS / run from the Command prompt.

Andy G4JNT