free 1-16 pill amp plans

[AudioShockwav]

By trial and error.
One issue is that HG uses the same lot number for everything, crusher has reported at least 3 different tunes.
It's not like the Toshiba transistors that you could roast half of a 16 transistor amp, replace the dead ones and go on .....
Toshiba had lots time to perfect the process, making a very consistent product.

73
Jeff

 

[Lost Ram]

if i want to use the 2, 4 and mabye 6 pill amp schematics posted here, how would i change the values of the capacitors and resistors to match the hg 2879 regulars?

I normally start with 560pf on the input transformer and 1000-1150pf on the output transformer. Output tune caps 140pf-150pf input tune caps 120pf-ish. Variable caps really help with this then install fixed after you get the tune right. 10 and 100 ohm resistors stay the same as do the 120pf beside the output transformer. This is just a starting point!!!!!!!! This is why I only repair HG boxes, guess I am still stuck in the past. Once I run out of real Toshibas I guess I will have to step in the HG thing.

 

[Hambones amps]

I normally start with 560pf on the input transformer and 1000-1150pf on the output transformer. Output tune caps 140pf-150pf input tune caps 120pf-ish. Variable caps really help with this then install fixed after you get the tune right. 10 and 100 ohm resistors stay the same as do the 120pf beside the output transformer. This is just a starting point!!!!!!!! This is why I only repair HG boxes, guess I am still stuck in the past. Once I run out of real Toshibas I guess I will have to step in the HG thing.

well i have 3 toshiba 2879 red dots, but i am scared to build with them. i have built 2 hg 2879 4 pills and fixed many other amps but i cant calculate the values of thing like that. but thanks alot.

 

[Lost Ram]

well i have 3 toshiba 2879 red dots, but i am scared to build with them. i have built 2 hg 2879 4 pills and fixed many other amps but i cant calculate the values of thing like that. but thanks alot.

You can buy them a ICA along with many other amp building items.

 

[Hambones amps]

You can buy them a ICA along with many other amp building items.

thanks. one more question. where could i get a schematic for a 3 pill (1 driving 2) of toshiba 2879 red dots?

 

[Lost Ram]

thanks. one more question. where could i get a schematic for a 3 pill (1 driving 2) of toshiba 2879 red dots?

 

[Lost Ram]

thanks. one more question. where could i get a schematic for a 3 pill (1 driving 2) of toshiba 2879 red dots?

R1, R4, & R5 4.7Ω 2W Carbon Film Resistor 3 Yellow-Violet-Gold
R2, R8, & R9 100Ω 2W Carbon Film Resistor 3 Brown- Black- Brown
R3, R6, & R7 10Ω 1/2W Carbon Film Resistor 3 Brown-Black-Black
VR1 100Ω 2W Potentiometer 1 Labeled
C1 100~180 pf Silver Dipped Mica Capacitor 1 100~180 / 500V
C2, C3, C4, & C9 1000 pf Silver Dipped Mica Capacitor 4 1000 or 102 / 500V
C5, C6, C7, & C8 .1 uf Ceramic Disc Capacitor 4 104 or .1
C10, C15, & C16 120 pf Silver Dipped Mica Capacitor 3 120 or 121 / 500V
C11, & C12 .01 uf Ceramic Disc Capacitor 2 103 or .01
C13 330pf Silver Dipped Mica Capacitor 1 330 or 331 /500V
C14 820pf Silver Dipped Mica Capacitor 1 820 or 821 / 500V
C17 150 pf Silver Dipped Mica Capacitor 1 150 or 151 / 500V
C18 22 uf Electrolytic Capacitor 1 22 uf / 25V
C19 22 pf Ceramic Disc Capacitor 1 22
C20 .03 uf Silver Dipped Mica Capacitor 1 Large Cap. (Not Labeled)
VC1 Trim Capacitor 1 465
D1 3A / 1000V PIV Silicon Rectifier 1 1N5408
D2 1A / 1000V PIV Silicon Rectifier 1 1N4007
D3 Glass Signal Diode 1 1N4148
D4 LED Indicator assy. 1 Blue LED / Resistor Pkg.
TR1 Driver Section Power Transistor 1 SD1446 / 2SC2879 (See Note)
*Above transistor depends on which model is being constructed – SD1446=450V+ / 2SC2879=450V+ HDV
TR2, & TR3 250 Watt RF Power Transistor 2 2SC2879
TR4 Switching Transistor / TO-92 1 PN2222A
CHK1, 5, & 7 ½” x ½” Ferrite Core 3
CHK2, 3, 4, & 6 ¼” x ½” Ferrite Core 4
T1, T3 ½” x ½” Ferrite Transformer Core 2
T2 ½” x 1” Ferrite Transformer Core 1
T4 ½” x 1-1/4” Ferrite Transformer Core 1
SW1 SPST Switch 1
RLY1 DPDT Relay 1
FAN1 3-1/4” Fan Assy. 1
Page 1
Designator Description QTY Code Check
FG1 3-1/4” Fan Guard 1
Conn1, & Conn2 Panel Mount SO239 UHF Connector 2
Conn3 ¼” Stereo Phone Jack 1
Cabinet Aluminum Enclosure Assy. w/ Bracket 1
HS1 Aluminum Heat Sink 1
CB1 Pre-Drilled Copper Clad Circuit Board 1
CB2 Copper Clad Circuit Board 1” x 1” 1
PS1, 2, 3, & 4 Pre-Cut Transistor / Pill Strips 4
SCK1 LED Mounting Clip (Packaged w/ LED) 1
KB1 Control Knob 1
WIRE-1 9-1/2” Length of #14 Silver/Teflon Wire 1
WIRE-2 37” Length of #16 Silver/Teflon Wire 1
WIRE-3 23” Length of #20 Silver/Teflon Wire 1
WIRE-4 18” Length of #20 Hook-up Wire (Color 1) 1
WIRE-5 21” Length of #20 Hook-up Wire (Color 2) 1
WIRE-6 19” Length of #12 Power Cable 1
COAX 8-1/2” Length RG316 Coax 1
HDW1 Hardware Kit (See Below)
SHCS #4 40 x ¼” Socket screw 8
SHCS #6 32 x ¼” Socket screw 12
Pan Head Sheet Metal Screw 2
Pan Head Machine Screw #6 32 x ½” 4
#6 Lock Washer 2
#6 32 TPI Machine Nut 4
#6 Solder Lug 3
Pan Head Machine Screw #8 32 x ¾” 4
#8 Lock Washer 3
#8 32 TPI Machine Nut 4
Rubber Feet 4
Rubber Grommet 1
Scrap circuit board material 1
Heat sink lubricant 1
Label Sheet 1

 

[Lost Ram]

thanks. one more question. where could i get a schematic for a 3 pill (1 driving 2) of toshiba 2879 red dots?

Also note the red dots are just made of a safer material and do contain beryllium. Either build with the same specs but the non red dots cool better because of the beryllium. You can even mix them, I have done that many times if the HFE is similar. Lot numbers with Toshiba does not seem to be a big deal either, done that too seeing they are hard to get these days. Anyone correct me if I am wrong here.