technical manual for sailor compact hf ssb t2130 - Gopher Proxy

5.2 OUTPUT FILTER (MODULE 2) PART NO. 625642
From the power amplifier the signal is fed to the output filters. There are six seventh order filters.
These filters attunes all harmonics so that they are more than 43 dB below the fundamental frequency.
The filters cover the following frequency bands:
filter No. 1 covers 1.6 - 2.5999 MHz
filter No. 2 covers 2.6 - 4.1999 MHz
filter No. 3 covers 4.2 - 6.7999 MHz
filter No. 4 covers 6.8 - 11.0999 MHz
filter No. 5 covers 11.1 - 18.0999 MHz
filter No. 6 covers 18.1 - 29.9999 MHz
Each filter is a duplex filter. The filters allow the fundamental frequency to pass through and feed the
harmonics to the 100 ohm loads. This gives a good load match for the power amplifier.
From the filter the signal is fed through a directional coupler TR01. C31 is used for adjustment of the
balance of the directional coupler.
The forward voltage and the reverse voltage is first rectified in a quasi effective value rectifier (VF: D09,
R07, R09, and C32. VR: D10, R08, R35, and C33), then in a peak rectifier (VF: U01/3, D11, R15, R13,
R11, and C36. VR: U01/4, D12, R16, R14, R12, and C37). Finally they are buffered in a unity gain amplifier
(VF: U01/2, VR: U01/2). The signal from the two buffers is then fed to the TX processor.
From the directional coupler the signal is fed to RE13, RE14.
The function of the relays is:
1. RE13 and R14 not activated (receive mode).
Connects the RE2100 (RX) J03 to the antenna (AT2110) J04.
2. RE13 activated and RE14 not activated (transmit mode).
Connects the RE2100 (TX) J03 to PA input J02.
3. RE13 and R14 activated (output power setting).
Connects the RE2100 (TX) J03 to R27, R28 50 ohm dummy load. This function is used for
automatic power setting. See also circuit description for TX processor module 3.
PAGE 5-5