b k 1000

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DJ9PK SWR Meters - This device was designed as an SWR and power meter for Radio Amateurs. In addition to SWR, it measures forward and backwards power, therefore can also be used as a wattmeter. With a large measuring range from 1 to 1000 watts, it is suitable for use from QRP to QRO
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SM1000 FreeDV Adaptor - The SM1000 allows you to run FreeDV without a PC. Connect the SM1000 to your SSB radio, and you now have Digital Voice (DV). You don�t have to buy a new radio to run Digital Voice! It�s based on a STM32F4 micro-controller, has a built in microphone, speaker amplifier, speaker, and transformer isolated interfaces to your radio.
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Recognition of CW signs at different listening levels and frequencies - The recognition of telegraphy masked by noise at 40 and 80 signs/min telegraphy speed was studied in 10 normal-hearing subjects at different sound pressure levels (25-85 dB SPL in steps of 5 dB) as well as at different test frequencies (2000, 1000, 800, 630, 500 and 250 Hz). The ability to recognize the signs varied with varying SPL. Recognition for most of the subjects was best at an SPL close to 70 dB. All subjects improved their recognition as the frequency was lowered to 500 Hz, some even at 250 Hz. These facts should be taken into consideration when training telegraphy operators as well as in the construction of radio receivers to permit listening at low frequencies. Furthermore, the critical ratio was calculated at the different test frequencies.
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Repair of an FT-1000 MP Mark V - Repair of a Yaesu FT-1000 MP Mark V probably struck by lightning.
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FT 1000MP MK V and Keyclicks - YaesuFT1000MK V stands out with improved close-spaced SSB transmit performance, reversing a trend seen in other modern radios. Featuring a class-A mode, it offers clean HV finals when kept out of ALC. However, two significant flaws persist: the noise blanker causes receiver IM distortion, and the transmitter lacks wave-shaping on CW, resulting in pronounced keyclicks. Preliminary tests reveal strong keyclicks +1kHz and -1kHz, prompting a combined modification to address both issues.
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