Kenwood TS-870S Noise Blanker, AIP Advanced Intercept Point, Attenuator, Setting Spac Time

			8 REJECTING INTERFERENCE
NOISE REDUCTION (SSB/CW/FSK/AM)	contest-type conditions, on an extremely crowded band,
Menu No. 13 (LINE.ENH) determines whether the Line	or when propagation is at a peak and all signals are
	local quality.
Enhance function (an adaptive filter) or the SPAC filter is	¥	Press [AIP] to toggle the AIP function ON or OFF.
used. When using the Line Enhance function, switch
Menu No. 18 (TRACK) to ON. The SPAC filter works	¥	ÒAIPÓ lights when the function is ON.
better for reducing noise and is effective for eliminating
various types of noise. However, audio quality will
deteriorate since only the audio portion is selected. This
filter may induce pulse noises. One difference between			AIP AGC AUTO
the digital Line Enhance function and the conventional
analog-based Noise Blanker is that the digital function			CW
works at audio frequencies whereas the blanker acts at
IF.	¥	By default, AIP switches ON for all frequencies
Press [N.R.] to toggle the Noise Reduction function ON
		below 7490 kHz. However, the status of AIP is
or OFF.		stored independently for each AIP band. When a
¥ The LED indicator in the button lights when the		different AIP band is selected, the last setting
		(OFF/ON) used on that band is recalled.
function is ON.
¥ When the S/N ratio is reasonably good in SSB, using	Note: If you are concerned about precise S-meter readings, switch
	ON Menu No. 11 (AIP.GAIN) when using this function. AIP.GAIN
Line Enhance will improve the S/N further. When
	does not change the S-meter sensitivity but, due to the increased
receiving a CW signal with a poor S/N ratio, using	gain, the noise level increases even while receiving no signals.
SPAC will improve the S/N. For AM signals,	AIP.GAIN does not work in FM or AM.

received audio may become intermittent.

SETTING SPAC TIME

SPAC is a DSP term that literally means Speech Processing using Automatic Correlation. This is one method of digitally filtering out noise. Using Menu No. 15 (SPAC), select the correlation time that provides the highest quality reception for SSB. When receiving CW, choose the longest time that allows reliable reception. The longer the correlation time, the better the S/N .

NOISE BLANKER

The Noise Blanker was designed to reduce pulse noise such as that generated by automobile ignitions.

Press [NB] to toggle the Noise Blanker ON or OFF. To change the level of blanking, adjust the NB control. Always use the minimum necessary blanking. This reduces the chances of blanking your desired signal.

¥ÒNBÓ lights when the function is ON.

AGC AUTO	NB
	WIDTH

USB

¥When receiving a strong signal while the Noise Blanker is ON, receive audio may sound distorted. Eliminate the distortion by reducing the Noise Blanker level, or by switching OFF the function.

AIP (ADVANCED INTERCEPT POINT)

AIP helps eliminate interference and reduce audio distortion that is sometimes caused by the presence of strong signals. AIP is especially useful during

ATTENUATOR

The Attenuator prevents distortion by reducing the level of the receive signal. The function is also useful to reduce interference from adjacent frequencies.

Press ATT [DOWN] or ATT [UP] to select the desired attenuation.

¥The selected attenuation (units of dB) lights (ÒÐ ATT Ð 6Ó, ÒÐ ATT Ð 12Ó, or ÒÐ ATT Ð 18Ó).

AGC AUTO

LSB

¥The status of ATT is stored independently for each ATT band. When the ATT band is changed, the last setting used on the band is recalled.

Band	Frequency Range		Default AIP	Default ATT
No.	(MHz)		Setting	Setting
1	Lowest freq. ~ 2.49		ON	OFF
2	2.49	~ 4.49	ON	OFF
3	4.49	~ 7.49	ON	OFF
4	7.49 ~ 10.49		OFF	OFF
5	10.49 ~ 14.49		OFF	OFF
6	14.49	~ 20.99	OFF	OFF
7	20.99	~ 21.99	OFF	OFF
8	21.99	~ 25.49	OFF	OFF
9	25.49 ~ 30		OFF	OFF

Note: The lower limit is inside the band in each case; the higher limit is inside the next higher band. For example, 4.49 MHz is in Band 3 whereas 7.49 MHz is in Band 4 (exception: 30 MHz is in Band 9).

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