Discussion in 'General Technical Questions and Answers' started by KC9E, Sep 28, 2002.
CAN ANYONE TELL ME JUST WHAT IS CLOVER AND WHAT IS THE PRINCIPLE OF OPERATION?
Just a suggestion:
I don't know what clover means in ham radio. I did take a minute and went on Google.com and searched clover. Well, that brings up zillions of things that don't deal with ham radio. I searched all those results and added ham. Again, many different things did come up, but one describing clover in ham radio was on the first page of results.
You can find just about any answer you want by searching the Internet. Put in a word that you are not sure of and so many places will give you great detail of what it means.
a digital mode similar to amtor .... Hear it at http://www.wunclub.com/sounds/#clover
73 Bill WJ5O
From NB6Z page.....
CLOVER is a PSK mode which provides a full duplex simulation. It is well suited for HF operation (especially under good conditions), however, there are differences between CLOVER modems. The original modem was named CLOVER-I, the latest DSP based modem is named CLOVER-II. Clovers key characteristics are band-width efficiency with high error-corrected data rates. Clover adapts to conditions by constantly monitoring the received signal. Based on this monitoring, Clover determines the best modulation scheme to use.
73 Bill WJ5O
Clover is a great digital mode. You will need a Hal modem to operate it. It's used for ragchewing or moving data at about 750 b/s which is pretty speedy for HF (compare to 100 b/s for Amtor and 200 b/s for PACTOR).
If you want to listen to it, check out 14.065 LSB which is where all the US clover ops hang out. Kinda sounds like a bunch of frogs hihi.
Most of the users are rag chewers, but there are also some who xfer smaller digital files, mostly pictures.
Hope that helps a bit.
CLOVER is a digital communications mode that conveys 8-bit digital data over narrow-band high-frequency radio. It can also transfer ASCII text and executable computer files without using the additional control characters required in other digital modes, which decrease throughput. The system was originally developed by Ray Petit, W7GMH, and marketed by HAL Communications.
The original modem was named CLOVER-I, the latest DSP based modem is named CLOVER-II. It sounds like a "canary" when transmitting. A signal consists of a 1s burst + a long 20s data transmission. Clovers key characteristics are bandwidth efficiency with high error-corrected data rates. Clover adapts to conditions by constantly monitoring the received signal. Parameters which can affect quality and reliability of the transmission such as block data errors, phase dispersion, frequency offset, and signal to noise ratio are monitored. Based on this monitoring, Clover determines the best modulation scheme to use.
The mode has been popular for maritime, military and commercial applications. Here is the 1992 CLOVER specification (HAL web site)
You can read more about the CLOVER 2000 and CLOVER II at the Ham Communications web site.