. Rare and Ancient Equipment MFJ-812 and 810 free download

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INTRODUCTION The MFJ-810 and MFJ-812 VHF SWR/WATTMETER a r e low l o s s meters p r i m a r y designed f o r 2 meter operation. However i t w i l l f u n c t i o n down t o 2 1 MHz w i t h reduced sensitivity.,,hhe MFJ-812 a l s o has a f i e l d s t r e n g t h c i r c u i t b u i l t - i n t o m o n i t o r RF r a d i a t e d s i g n a l s . INSTALLATION 1. Connect a coax c a b l e from t h e t r a n s m i t t e r t o t h e coax connecter on t h e meter marked " TRANSMT. TTER" I 2. Connect the antenna cable t o t h e coax connector i n t h e meter marked "ANTENNA". OPERATION 1. SWR Measurement: A) S e t t h e FS/SWR b u t t o n t o OUT f o r SWR. (For model MFJ-812 o n l y . ) B) S e t the FWD/REF b u t t o n OUT. Transmit a continuous c a r r i e r and s e t the SWR/ POWER c o n t r o l f o r f u l l s c a l e d e f l e c t i o n . C) Push I N t h e FWD/REF b u t t o n and read SWR. NOTE: The SWR s e n s i t i v i t y must be r e s e t when power l e v e l i s changed This w i l l . m a i n t a i n an accurate SWR reading. 2. Power Measurement: A) S e t the FS/SWR b u t t o n OUT (For model MFJ-812 o n l y ) . B) S e t t h e FWD/REF b u t t o n OUT. C) S e t the SWR/POWER c o n t r o l t o t h e 30 mark. This s c a l e reads a maximum o f 300 w a t t s . - -- - -- NOTE : T k . ft i s f a c t o r y -- - cal i l m t h is control . However, due t o component t o l e r a n c e when p r e c i s i o n reading i s desi red, t h e 300 w a t t range can be r e c a l i b r a t e d as f o l l o w s : S e t t h e FWD/REF b u t t o n OUT. (Set t h e FS/SWR b u t t o n OUT on the MFJ-812.) S e t t h e SWR/POWER c o n t r o l t o 30, n o t e t h e power l e v e l on t h e 30 w a t t scale, then r o t a t e the c o n t r o l t o read t h e same power l e v e l on the 300 w a t t sca'?. Mark t h e c o n t r o l s e t t i n g f o r t h e r e c a l i b r a t e d 300 w a t t range. FIELD STRENGTH