开云体育

There are two distinct tune modes with the BCC540G

?

The first one is the standard initiate tune by momentarily breaking and restoring the DC supply on Pin C and then applying at least 1w of RF the tuning sequence will then complete or stop at the nearest point to a correct tune.

?

The second method if used with a suitable radio e.g BCC39 is for the set to send a PWM serial control word to select one of 128 memory locations. This is what the battery is for to keep those memories active.

?

If DC power is removed from the ATU then the current tune position is lost and on re-applying the DC supply then one to the above procedures is needed to activate the tune again.

?

Hope this makes sense

?

Regards

Dave g1jwg

?

?

Dave,

?

Thanks for your response.

?

Just to be clear when using the momentary break method no data is stored. Tuning data is only stored when using the PWM method. Is this data still stored when the unit has no supply e.g. when the connected radio is powered off?

?

Richard

?

G7RVH

Hi Richard

?

The momentary break method does not store any data, each time it is initiated it resets the microprocessor and completes an active tune cycle with RF to match the antenna as best it can.

?

When a PWM data word is sent from a suitable radio the BCC540G checks to see if it already has it in memory, if not it it completes an active tune cycle with RF to match the antenna as best it can.

?

If the 8 bit PWM data word is in memory it checks the first bit which will either initiate an active tune with RF by recalling the capacitor and inductor settings stored in one of the 128 memories or indicate a passive tune (silent tune no RF) by recalling from one of the 128 memories the relay settings for capacitors and inductors.

?

The memory which holds the capacitor and inductor relay settings is RAM which is held up by the battery so that information remains stored.

?

When DC power is removed from the unit the relays and CPU reset so the current tune status is lost and tuning will need to be reinitiated on power on with either an active tune or passive tune described above.

?

This is also the case for the BCC540C and BCC540F

?

?

Regards

Dave g1jwg

?

Dave,

?

Many thanks for your clear and informative response. I now understand what is going on with the Syncal 2000 / VIU / 540G combination that I have.

?

Also, the information regarding the other C & F variants is equally useful.

?

Richard

?

G7RVH

?

?