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AF and RF generator output level "off" indication.

By VK3NH •  2017-01-23 16:22:30 •  1027 clicks
The play pointer and stop square indicators are sufficient for VNA modes, DTF and spectrum analysis because you can easily see the device is operating by the sweeping action of the display.

This is not true for the AF and RF generator functions. I have been trapped a number of times looking for the level I have set up on the KC901V on another instrument , checking cables for faults when I did not get a result only to find the generator output is off as per the first picture below as indicated by the small square stop indicator.

and the output is on as per the small pointing forward arrow play indication in this next picture. There is nothing else to indicate whether the generator is working or not.

I suggest that when the output is off that the output display level be made to pulse on and off at the rate of about one pulse per second to warn the user that the level is not being supplied. This is the same as used in many VCRs and DVD players in the past when they were in pause mode which is what the mode effectively is.

This would be particularly useful in the field because there are many other factors which could lead to you not seeing a signal at the receiver or device you are testing.


Modify the AF and RF generator programs to pulse the output level indication when the output is off including when you are adjusting the level and it is highlighted.

regards Noel

instrument  sufficient  indicate  because  another 

9 Reply | until2018-11-18 13:32Add a reply
    VK3NH  189 days ago#1 -Reply

    Can you please provide a response to this request. It does not require a hardware change but it does affect device functionality and ease of use by the end user.

    The presence of the output signal in AF or RF generator modes is not currently indicated sufficiently.

    This could be fixed by a programing change to indicate the output is of by:-
    1/ Flashing the output level setting OR
    2/ Changing the level setting colour to red when it is not on.

    This issue has been noted in feedback from many users of the various KC901 models.

    If there is a reason why this simple software changes proposed at 1 or 2 cannot be made then please advise that.

    regards Noel

    VK3NH  2017-12-12#2 -Reply


    VK3NH  2017-12-09#3 -Reply

    Genuine post.

    This topic still has relevance and the comment is made in two of the four reviews you have for the KC901V. I am just after a response please, can the output level indicator or value be made to flash (or change colour) when the output is switched OFF?

    It is clearly capable of being done and is just a software change. but there might be some reason why you don't want to implement it such as increased battery drain. If that is the case then you could also make it a feature that is user enabled because personally I find that using AF o RF generator mode without a better indication than the small square (for stop) or arrow (play for go) is not sufficient. A blinking or changed in colour output level value would alert the user instantly that they need to press the RUN button.

    regards Noel

    VK3NH  2017-11-18#4 -Reply

    Since there have recently been responses to a number of "old" posts, can you please provide one for this.
    I am not the only one who has noticed the difficulty of working out if the signal generator or audio source is working or not when you change the frequency or level. It is noted in the reviews and it only involves a software change.

    If the level indication flashed when it was in stop mode then that would be perfect.

    Thanks - Noel

    VK3NH  2017-06-25#5 -Reply

    Please keep this suggestion for a software change under consideration. It helps avoid confusion when using AF and RF signal generator functions. The fact the unit defaults to generator off at times to save battery capacity is fine but the user needs to know that they should not be expecting an output.

    VK3NH  2017-05-06#6 -Reply


    Hi again,

    I would appreciate a reply telling me if this change can be made. Flashing the AF or RF generator output level indication would be a clear indication to the user that there is no output. Then the operator could take the appropriate action and press run.

    regards Noel

    VK3NH  2017-04-11#7 -Reply


    Can you please give me an indication if the recommendation above can be implemented?

    regards Noel

    VK3NH  2017-03-22#8 -Reply


    VK3NH  2017-03-03#9 -Reply

    Can you please comment on whether this feature could be included?


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