M207 — Phantom Power Card

M207 PHANTOM POWER SUPPLY The M207 Phantom Power Supply is 24 volt to 48 volt dc to dc converter_ This is achieved with push-pull relaxation oscillator and voltage doubler circuit. 01 through 04 form the push-pul relaxation oscillator which operates at nominal frequency of 100 kHz . RL is adjusted t0 give symmetrical oulput at the collectors of 01 and 03 . The peak t0 peak AC voltage on the collectors of 01 and 03 is in the order of 20 volts_ The voltage doubl Iing action is achieved by pre-charging CB to the 24 volt supply voltage through CRI, CR2 and CRJ. The rectified 20 volt P-p AC voltage is then added via C6, CR2 CR3 The net effect is t0 charge c8 to approximately 55 volts 05 is series Pass regulator with its dc outpul voltage set by zener diode CRL. The 48 volt dc output voltage i5 additionally filtered by c1o CRS ci. 1-1

WAAD-BECK SYSTems LTD_ PARTS LiST M207 2LV to 48V CONVERTER PART DESCRIPT ION MFG MFG PART NUMBER C1 C2 C3 CL C5 Capacitor 100 uF/40 V 2200 pF /630 Philips 426ETG100 347CGA2K2 C6 C7 c8 c9 cio uF/250 uF/250 22 uF/63 3L4ABIM 344ABA|Ok 426ETH22 C11 C12 C13 C14 C1s 2.2 uF/63 27 pF 344BHA 2M2 2222-638 58279 CRI CR2 CR3 CR4 CRS Diode Motorola JNLOO3 Zener TR Motorola INL757A IN4003 FI 0.25A FB Buss AGC 1/4 01 02 03 04 05 Transistor National Motorola National Motorola 2N4037 2N2101 ZN4037 2N2102 RI R2 R3 RL RS Resistor 1/*2w 5% 47 Philips Trim Pot Resistor 1/4w 57 12k Piher Philips PTiOh (2.5) Sk R6 R7 R8 R9 R1o 33K 33K ISK Resistor 1/2w 5% 4.7 Philips 2-1 Fuse

WAAO-BECK Sybtems LTD PARTS LiST M207 24v L0 48vCONVERTER PART

M207 PHANTOM POWER SUPPLY The M207 Phantom Power Supply volt volt dc dc converter. This achieved with push-pul l relaxation oscilator and voltage doubler circuit. through 04 form the push-pul relaxation oscillalor which operates at nominal frequency 100 klIz . R4 adjusted 9ive symmetrical oulput the collectors Q1 and 03 . The peak peak AC voltage on the collectors and 03 the order of 20 volts The voltage doubling action achieved by pre charging CB tne volt supply voltagc through CRI,CR2 and CR3 .

The rectified vol P-P AC voltage [hen added via C6, CR2 CR3 The net effect charge c8 approximately volts 05 series Pass requlator with its outpul voltage set by zener diode CR4 The volt dc output voltage additionally filtered by C1o CRS Ci_

MFG MFG PART NUMBER RII R12 Resistor 1/2w 5% Resistor /4w 5% 10k Philips Fuse Holders Littelfuse 102068 Transistor Heat Sinks Birtcher 34L716 Ferrite Beads Philips VK21029/3B WBS recommend the use replacement parts made by the specified manufacturers Tor continued optimum equiprent performance 2-2