ToyX project EQ Linearizer study case5

Put L channel EQ module and check out the hole of screws.


Assemble copper cylinder prepare for put on R channel EQ module.


Check out two channel EQ modules structure.Meet design or not.


Another view.


Assemble Fuse,RCA connectors,Volume knob,power switch.

Finish wires jump between each band and volume knob.

Another view.

Toy11 VT4C 211AMP -2

After estimate placement too many components so I decide to build mono mono amp.
Drill holes for mount component.
Rectifier tub is 5U4G.
Signal driving tub 6C45pi.
Amp tub VT4c-211.


High voltage for 211 plate voltage I usage C-L-C balance circuit .
Two chocks one is for 211 B+ another for GND.


Top side picture.
Left corner is OPT.
Right corner is High voltage transformer and heater transformer.


Rear view.


C-L-C High voltage I cascade 3 capacitors for 1800V (no Tub insert).



High voltage I usage 2 times frequency boost to 1600V.

ToyX project EQ Linearizer study case4

Finish each band circuit by jump wire.

Finish EQ power circuit and do placement estimate.


Test two bands EQ function together (by cascade).


Feed SG signal in band 4 for function test.


Measure output signal form band 5 and estimate circuit where need modify for meet design.


Band 4 top view.


Today receive EQ box order from two month ago.
This is front view with ten volume knobs. Each channel with five knobs to control EQ.


Inner picture.



Rear picture.

Toy11 VT4C 211AMP -1

Start to prepare the component and box.


Estimate the placement for good signal and easy hand make.



Estimate placement picture.

ToyX project EQ Linearizer study case3

Tuning each inductor value for meet LC band pass filter.


Finish each band pass  structure.


Test each band the frequency of drift .


Side view picture.

Estimate EQ  Linearizer outline and prepare drawing  of  EQ case.

Turntable test machine

All testing utility

VCO arm of pick up.

Detect pin1 & rotate VCO.

VCO RF test head.

VCO arm pick off.

Put  VCO in tub of  roller.

Detect sensor.

VCO test handle.

ToyX project EQ Linearizer study case2

Placement Band pass filter.


Solder capacitor of band pass filter.


Estimate placement.

EQ Linearizer  will be mono mono stack by two layer.