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			May 16, 1980
HM-2140						Bulletin No:
HF Dual Wattmeter					HM-2140-1

			  Inoperative

++++Information not available at this time++++
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			August 13, 1980
HM-2140						Bulletin No:
HF Dual Wattmeter					HM-2140-2

	                Battery Meter Pegs And Unit Will Not Null

++++Information not available at this time++++
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			January 27, 1984
HM-2140						Bulletin No:
HF Dual Wattmeter					HM-2140-3

		            PEP Readings Inaccurate

Make the following changes to the remote sensor and main unit.  Recheck
the calibration after installing these changes.  New production will have
these changes included.

Remote Sensor [PN 100-1749]:  Change C106 and C107 to .0027 uF [PN
27-141].

	Do not disturb any control settings after making the change.  Be
sure
	to reseal the sensor using a service sticker.

Main Unit:  Change:  	C17 to .022 uF [PN 27-128]
			C18 to .033 uF [PN 27-138]

Note:  The only accurate method of checking PEP calibration is by using a
two-tone test generator.  The FCC standard tones for the two tone test
are 400 Hz and 1800 Hz.  A whistle represents only one tone and will give
the same output as a steady carrier [CW] signal.  Voice modulation may
give a slightly different reading since the voice is composed of many
tones.  The PEP readings should be very close if the AVERAGE power
readings are close. [PEP does not have an accuracy specification.]
--------------------------------------------------------------------------------------------------------------------Thats
everything I hold up to 1987 that covers the HM-2140 HF Dual Wattmeter.
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