Vhf-1200 / vhf-2000 6 m linear amplifier owner’s manual palstar, inc. Command technologies division 9676 n. Looney road piqua, ohio 45356 u.S.A. Customer service and sales telephone: 800-773-7931 international: 937-773-6255 fax: 937-773-8003 e-mail: info@palstar.Com.
2 table of contents introduction 3 specifications 4 unpacking instructions 6 installation preparation 6 hv transformer installation 7 safety warnings and precautions 8 connections 9 operating procedure 9 typical operating conditions 11 circuit description and adjustments 12 tuned input & t/r relay s...
3 introduction the commander vhf-1200 and vhf-2000 are grounded grid class ab 2 linear power amplifiers that operate on the amateur 6 meter band. Over-drive and over-grid current protection is provided by an auto-reset circuit that places the amplifier in standby if a preset grid current limit is ex...
4 specifications commander vhf-1200 6 m linear power amplifier • modes: usb, lsb, rtty, fm, & cw • power requirements: 200/234vac 50/60 hz. • rf drive power: 15-25 w nominal; 35-40 watts max. For full output (1.2 kw pep on ssb) • rf output: 750 w maximum, fm or rtty • input impedance: 50 ohm unbalan...
5 specifications commander vhf-2000 6 m linear power amplifier • frequency range: 50 to 54 mhz • modes: usb, lsb, rtty, fm, & cw • power requirements: 200/234vac 50/60 hz. • rf drive power: 15-25 w nominal - 35-50 w max. For full output (1.5 kw pep on ssb ) • rf output: 1500 w maximum, fm or rtty • ...
6 unpacking carefully remove your vhf-1200/vhf-2000 amplifier from its shipping carton making sure there is no damage evident from shipping. If there is any damage, notify the delivering shipper immediately, fully describing the damage. The hv power transformer was shipped separately, as its weight ...
7 grip the transformer by the windings, as shown. There is not enough room for your hands inside the cabinet if you hold it by the base. Carefully lower the transformer into the amplifier. Be careful not to bump the backs of the meters and be sure the connector plug is out of the way and will not be...
8 caution: • do not attempt any type of service or repair on this amplifier without first removing the ac power and allowing at least 60 minutes for the high voltage capaci- tors to bleed off ! • do not operate this amplifier with the top or bottom covers removed. Do not operate this amplifier with ...
9 connecting your amplifier locate your commander vhf-1200/2000 so that no equipment is directly above it, as air expelled from the tube exhaust on top can become quite hot. Allow at least 3 inches clearance on either side between the unit and other objects or equipment. Connect the rf output of you...
10 switch the operate / standby switch to operate and key the exciter with zero rf drive applied. The red transmit light should come on, along with an indication of plate idling current on the meter (approx. 100-160 ma vhf-2000; 80-100 ma vhf-1200). Apply a low level of rf drive (5 w or less) and ad...
11 drive grid current plate current power output 12.5 watts 20ma 400ma 450 watts 18.5 watts 30ma 500ma 650watts 30 watts 50ma 600ma 1000watts drive grid current plate current power output 25 watts 30ma 700ma 1000 watts 40 watts 45ma 1000ma 1500 watts typical operating conditions vhf-1200 typical ope...
12 circuit description and adjustments the commander vhf-1200/2000 uses genuine eimac 3cpx800a7 ceramic/metal triodes) in a class ab 2 grounded grid configuration. Nominal drive power of 35 to 50 watts will deliver full rating of clean rf output power. Metering functions the commander vhf-1200 and v...
13 tuned input circuits the tuned input circuits utilize an l-c-l or "t" impedance matching circuit with a high q design. These circuits employ rf phase compensating inductors to reduce intermodulation products. The use of mica trimmer type capacitors allows adjustments to precisely match the transc...
14 tuned 6 m input t/r relay.
1 5 control board.
16.
17 hv power supply.
18 rf deck.
19 rf deck.
20 limited warranty palstar inc. Warrants the vhf-1200 and vhf-2000 to be free from defects in material and workmanship under normal use and service to the original buyer for a period of one (1) year from the date of delivery to that buyer (the “warranty period”). Palstar inc.’s obligation un- der t...
