VFO - ZL1CVD DDS - Assembled...
ZL1CVD DDS module fully assembled and tested. You buy or make a case to suit your transmitter. Powered from your transmitter filament or low voltage supply (you must rectify it. anything from 6 to 12v: 12v may need a heatsink on the regulator.). I have some SMA to N and SMA to SO239 connectors etc... Firmware and some nice pictures of an Italian ham's use of the VFO can be found in the Technical Data link on this site under DDS or on Chris's site -
This DDS VFO module is ready to use and makes an ideal external VFO project for older HF transceivers. It is compact, very stable, easy to set up and use.
You can also use it as a frequency generator or reference!
Very easy to use as an external VFO alternative for:
Yaesu: FT-101, FT-102, FT-107, FT-301, FT-901, Ftdx400, Ftdx500, Etc
Kenwood: TS-120, TS-130, TS-180, TS-520, TS-530, TS-820, TS-830, TS-900
A highly accurate and stable replacement for:
Yaesu: FV-101, FV-102, FV-107, FV-301, FV-401, FV-901
Kenwood: VFO-120, VFO-180, VFO-230, VFO-240, VFO-520, VFO-820, VFO-900
To make a fully functioning VFO you will need:1) a suitable enclosure, 2) 4 x 1N4148 or equivalent, small signal diodes, 3) 4 SPST momentary contact push button switches, 4) a voltage source - in most cases a rectified filament supply or other 12v source will work fine.
Firmware Version 1.4 (ZL1CVD)
This is the standard version loaded on these assembled DDS's.
The frequency displayed on the LCD, is calculated as follows:
RX = Multiplier x (RX_DDS_FREQ + IF_OFFSET_FREQ +/- RIT)
TX = Multiplier x (RX_DDS_FREQ + IF_OFFSET_FREQ + TX_OFFSET_FREQ +/- RPT)
The frequency output by the DDS, is calculated as follows:
RX = ABS(RX_DDS_FREQ)
TX = ABS(RX_DDS_FREQ + TX_OFFSET_FREQ)
there are other options where the transmitter does not require an offset but the receiver does, or the display is required to display 1/2 the frequency.
There are cheaper VFO's on eBay, but this has been developed by, dare I say it, an Australasian amateur (yes.. I know he is from New Zealand.. look it up). You can buy it direct from Chris on eBay, or marginally cheaper here from me with cheaper local postage.. I am sure however, that Chris would be happy to sell you one direct!! If they are not in stock, I have some on order - so ask.... looks like March 2018 now..
$9.95 pack and post to Australian addresses.