R.V.R. Elettronica VJ3000, Инструкция по установке, техническому обслуживанию и ремонту

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R.V.R. ELETTRONICA S.r.l. (BO) Pag. 62
VJ3000 - Technical and Maintenance Manual
(N.B. Take great care not to break the interlock microswitches
which inhibit the unit).
6) Check, using a clamp ammeter (SETUP 2) that the filament current
is about 51.5 A.
7) Now, using a multimeter (2 Fig.3), check that the filament voltage
is 7.5V ±0.37V; and that VA is about 4800 V. Check the values in Table
E according to the type of tube being used.
8) Switch on the exciter and, when locked, increase the power output
to 20-25W.
9) Adjust the INPUT and GRID tuning controls (2 & 4 Fig. 4) to obtain
minimum SWR as read from the exciter PWR meter; the anode current
should increase simultaneously.
10) Adjust the PLATE control (5 Fig.4) to obtain minimum output power
and repeat with the LOAD control.
N.B. To preset the PLATE control use the table supplied with the
amplifier. This operation is performed measuring the length of the
threaded rods coming out of the chamber and adjusting them to the lengths
in Table F to correspond to the desired operating frequency (the
measurement should be made from the end of the front, right-hand rod).
Check that the threaded rods move towards the inside of the chamber
whenever the frequency moves towards 108 Mhz and that the rods move out
of the chamber when the frequency moves towards 88 Mhz.
11) Increase the driver power and re-adjust the PLATE and LOAD controls
(3 & 5 Fig.4) for maximum power. An output power of 500-600 W should
be obtainable using the PTX30-UHT exciter and the 3CX3000A triode.
12) Reduce exciter power to a minimum and connect the driver in series
with the exciter (eg. PJ250) (SETUP 3).
13) Increase exciter power once more and repeat the adjustments of PLATE
and LOAD for maximum output power, gradually increasing the input
power. Should the SWR on the VJ3000 input increase with power output,
re-adjust the INPUT and GRID controls to minimize the SWR.
14) Now adjust the driver level and the LOAD and PLATE controls for 3KW
of output power. For all other parameters, refer to the calibration
tables supplied with the unit. Note that the maximum permissible
values are:
IA = 1.3 A Ig = 400 mA