ToyX project EQ Linearizer study ....Battery Power

EQ Linearizer 電源是大問題,喇叭效率超過95dB時,100hz以下AC 60hz容易peak進去,over 4khz以上又容易有高頻訊噪,高音會ㄘㄘ聲,解了下面100hz訊噪,over 4k 訊噪不好解 ,所以用電池.





The Battery box usage 4 cells (2S2P) Li-ion output 8.2V/5.2A (peak current limited in 5A).
No fuse and auto Over current ,Low Voltage,Over Temperture protection.




The EQ Linearizer remote power circuit clamp chock to reduce EMI influence.
L Channel and R Channel power path add diode to separate cross influence.




The battery module could stand alone into charge mode . So no AC noise.

The battery cells will  separate to open and charging by single cell  charger therefor no unbalance issue.

Toy12 Plasma tweeter Diy-8

 211 Amp. take off old output transformer  and prepare assemble new output transformer .


Put two output transformer together.
Left side is Look-T OTP and Right side is Lite OTP from China.


Look-T transformer thickness is more large.


Find a suitable box and hand make an home give for  transformer.
This for Hi-pass across over (over 7Khz) change impedance to fit Plasma tweeter input.


Replace output transformer and verify function is ok.
Look-T 211 Opt 跟原先比起來清楚的多, 原先的 Otp 稍矇的分不是很清楚前中後的音像及細節.
低頻有下去些 較大差異是之前用Analog EQ.增加50hz,250hz的Gain,但是211會有些悶悶的打不出聲音,
現在完全沒這現象,像我300B的低頻聲音線條了.


Finish whole shielding net and verify Plasma tweeter radiation in working normal (about 650V@140mA).
The current will be about 150mA when audio signal modulation in.


Other angle picture.


Connect plasma tweeter of L,R channel and estimate real sound color.



Switching  A,B test sound color and verify different  between RP-302 and Plasma tweeter.

Battery Management System 電池管理系統 (BMS) Li-ion 60 cells inside ouput power 24V/26A

BMS Front View.
Build in 5 battery modules in a Battery box .


Each battery module could read out  voltage,current,temperature.



Remote access Program and read out battery module Voltage ,Current.

Toy13 D/A with tube amplifier

D/A High voltage use R-L-C-L-C net to generate 230V for Tube 6922 plate-voltage.
Rectifier is 6Z4 and put in delay-on function.


D/A output OP +15/-15V power supply by switching power.


Spdif receiver is CS8416 and Codec is WM8741.


All circuit design usage SMT components.
Serial audio path usage DIP components for high Q factor issue.


The view of Audio signal switching and audio-input of tube.


D/A Top view picture.


Add 6922 heater R & C components.



Add Tub output OPT for good sound.

Toy12 Plasma tweeter Diy-7

Prepare close shielding-net I buy a big heat sink from internet.
Heat sink drill holes for mount 120w resistors.


Measure pitch distance.


From rear side to Drill holes to fix heat sink.


Finish heat sink and resistors assembly at rear side.


Rear view.


Top view.
I put on a current meter for monitor high voltage.



Another picture.

Toy12 Plasma tweeter Diy-6

Order 120W VR for step down high voltage.


Put resistors on wood rack and finish high voltage connection.


After long time debug a tiny flaming just pop out.
So far I could make sure my circuit of RF TUB amp. is workable.
But I still need to tuning work voltage and current of PL519 to improve flaming make it large.



Zoom in picture.


Re-modify working voltage and current 480V and 0.2A.
No sound modulation in and Just carry frequency radiation.



Modify flaming size.

Toy12 Plasma tweeter Diy-5

After  check high voltage generate have a problem cause by step-down resistor.
Because PL519 will take 580V/200mA so resistor of step-down is hot .
Step down voltage about 250V by 0.2A ...74W.  Estimate need cascade a 200W resistor for low temp. profile operation.



Finish IF circuit high pass filter and measure modulation out about 105V ...in spec.
But ECL82 and 6C45pi Plate-voltage need check again when replace high voltage resistors.



Because RFC inductor is hard to buy on internet So I  use a 20 ohm resistor hand make a RFC.



Top view.

Hand make Ring wire for PL519 feed back circuit.

Toy12 Plasma tweeter Diy-4

This week finish audio amp. (6C45pi) and IF modulation (ECL82) circuit.


For good shielding reason I design to build a small space for IF module.
But this cause it's hard to hand make and modify circuit.


Finish IF high-voltage and prepare for 6C5pi,ECL82,PL519 heater test.
Meanwhile I measure PL519 (insert already) heater voltage only 36.4V.
I got check spec. of  PL519.  So far the transformer of heater  is one way ticket.



The PL519 heater light is turn on.

Toy12 Plasma tweeter Diy-3

Fix shielding net on front side and assemble power bottom panel.
Mid panel for fix volume knob.


Fix shielding net on rear side and assemble AC connector.
Mid panel for fix Audio in RCA jack.


High voltage Design in a delay on relay (about 10 sec.) for heater turn on first.
High voltage I usage 2 times frequency boost to 1000V then step down to about 600V.
Finish L channel C-R-L-C filter.


Finish R channel high voltage connection.
IF frequency high voltage about 500v than step down to 350V for ECL82 plate and setp down to 190V for 6C45pi plate-voltage.



Two times frequency boost to 1000V Rectifier tub is 5U4G.