Henry Radio 3K Classic Mark II Operating And Maintenance Manual page 9

across the contact you are using. If there is too much resistance, contact
the exciter's manufacturer about possible solutions to the problem.
SECTION 3.4 TRANSFORMER TAPS
The
amplifier is normally factory wired for 22(]-230 VAC, 3 wire, 60
Hz
operation unless specially ordered otherwise. If the AC mains are differ-
ent then you will probably have to make a modification in the power supply.
5o
HZ OPERATION - Unlike most other amplifiers on the market, most Henry
amplifiers use a resonant filter choke.
The choke is factory resonated at
60
Hz unless otherwise specified.
For 50 Hz operation a third resonating
capacitor must be added.
This will be done at the factory if specified at
the time of order.
FILAMENT TRANSFORMER
- The filament transformer is marked
EE'A 1226 (3!!
Classic) or
ECA 1194 ( 5K Classic).
They are factory tapped for
230
VAC
operation.
If the
AC line voltage is significantly different,
YOU must
rewire the taps on the transformer ( located in the power supply section).
E. CA 1 222 b
Tap 1 - Common----
Tap t - 200 VAC ---
Tap 3 -2 10 VAC ---
Tap 4 - 220 VAC----
Tap 5 - 230 VAC---
ECA 1194
Tap 1 - Common---
Tap 2 - ^00 VAC---
Tap 3 - 210 VAC----
Tap 4 - 220 VAC---
Tap 5 - 230 VAC---
Tap 6 - 240 VAC---
NOTE:
The nominal filament voltage at the tube is 7.5 VAC.
The amplifier
does
not meter filament voltage,
so you must use an external Al:: voltmeter
to
measure the filament voltage at pin jacks on the back panel of the RF
chassis.
The 3K Classic should measure close to 7.8 VAC at the pin jacks.
The 5K Classic
filaments
are in series and the voltage should read about
15.6 VAC.
becaf the voltage varies more than 5% from these figures, the
taps on the filament transformer should be changed.
HIGH
VOLTAGE
TRANSFORMER - The 3K C lassic Mark I I domestic amplifier is
supplied with the ECA 1120A. The primary tap connections are listed below:
ECA 1120A
--------------------------------
230 VAC --------------Tap 1
; ---.-.-Tap 3
: ----.--Tap 5
230 VAC---------------Tap 7
The 3K Classic X and 5K Classic are supplied with one of the following high
voltage transformers:
8