LUXKIT A3700 specifications LUXKIT / LUXMAN

LUXKIT A3700
¥ 48,000 (released in August 1978)

Commentary

Chassis kit for power amplifier that allows you to select output tube and circuit method according to your preference.

The A3700 consists of a universal high-capacity power transformer, a choke coil capable of handling high current, and a high-voltage block capacitor. With this chassis kit, you can select one of four tube panels (sold separately) according to your preferred circuit type, and combine it with an OY15 type output transformer, vacuum tube, resistor, capacitor, socket, etc. to complete a tube bulb power amplifier.

The output transformer of the OY15 series which is recommended to be used for the A3700 is available in two types of high-power push-pull type with reduced power loss by increasing the wire diameter, and two types of newly developed wide-band single type with less power loss.

8045G and 2A3 3-pole tubes and 6CA7 and KT-88 multi-pole tubes can be used. The output stage can be either a push-pull circuit or a single circuit. For multi-pole tubes, an ultra-linear connection is standard. A cathode NF circuit can be used in combination with a 3-pole tube connection.
However, when a large ST tube such as 2A3 is used as an output tube, it is not possible to construct a stereo push-pull circuit due to its shape and height, or it is not possible to install it with the bonnet as it is.

An assembly manual is included with the package. It includes wiring diagrams and adjustment methods for stereo push-pull circuits of 8045G, 6CA7, and KT-88, as well as recommended circuit examples for stereo push-pull circuits of 8045G, 2A3, etc. Leo Shin.

TCR-45
Recommended circuit parts set of stereo push-pull circuit by combining large 3-pole output tube 8045G jointly developed by LAX and NEC with high-power high-performance output transformer OY15-3.6K-HP with extremely low insertion loss.

The driver circuit uses a cathode-coupled phase-reversal circuit called the Mulard type, which uses Lux-brand high-voltage driver tube 6240G to create an excellent driver circuit.

When the TCR-45 is combined with the A3700, a stereo power amplifier with an effective output of 50Wx2 is completed.

TCR-A7
Recommended circuit parts set for stereo push-pull circuit combining 5-pole output tube 6CA7 which is well known as output tube for audio and new output transformer OY15-5K-HP of high power specification with very low insertion loss.

The output stage can be connected to an ultra-linear connection, an ultra-linear connection + cathode NF, or a 3-pole tube connection. The driver circuit consists of a cathode-coupled phase inversion circuit using Lux-brand high-voltage driver tube 6240G.

When the TCR-A7 is combined with the A3700, a stereo power amplifier with an effective output of 40Wx2 is completed.

CR-3700P
A CR parts set that includes resistors, capacitors, sockets, lug plates, and wiring materials to configure the recommended stereo push-pull circuit (described in the assembly manual attached to A3700) by combining the output tube such as KT-88 and OY15 type output transformer with A3700.

The connection method of the output stage can be selected from ultra-linear connection, ultra-linear connection + cathode NF, and 3-pole tube connection. The driver circuit consists of a cathode coupling type phase inversion circuit using Lux-brand high-voltage driver tube 6240G.

Tube panel is not included.

Model Rating

Type	Chassis Kit for Bulb Type Power Amplifier
Constituent part	Body	TCR-45	TCR-A7	CR-3700P
Constituent part	Power Transformer 9F380 Choke Coil #4705 Block capacitor 47uFx3/550V (3 pcs) Block capacitor 47uFx3/350V Bonnet Chassis Subchassis Bottom plate Pin jack terminal board Speaker terminal board Power switch Neon pilot Fuse holder Input level adjustment volume (2 pieces) DC Balance Adjustment Volume (2 pcs) Bias adjustment volume (2 pcs) Volume for a ham balancer Each volume mounting bracket (4 pcs) Mold Terminal Plate (5 pcs) Power cord Cord stopper Rubber Feet (4 pcs) Setting Knob (2 pcs) Itadori fittings Set of screws Assembly manual	3-pole Output Tube 8045G (4 pcs) Vacuum Tube 6240G (2 pcs) Vacuum Tube 6AQ8 (2 pcs) Output Transformer OY15-3.6K-HP (2 pcs) Tube Panel VP-1 GT Socket (4 pcs) MT Socket (4 pcs) Lug Plate (4 pcs) Coil (2 pcs) Diode (5 pcs) Resistor set Condenser set Wiring material set	5-pole Output Tube 6CA7 (4 pcs) Vacuum Tube 6240G (2 pcs) Vacuum Tube 6AQ8 (2 pcs) Output Transformer OY15-5K-HP (2 pcs) Tube Panel VP-1 GT Socket (4 pcs) MT Socket (4 pcs) Lug Plate (4 pcs) Coil (2 pcs) Diode (5 pcs) Resistor set Condenser set Wiring material set	Resistor set Condenser set GT Socket (4 pcs) MT Socket (4 pcs) Lug Plate (4 pcs) Coil (2 pcs) Diode (5 pcs) Wiring material set
Sold Separately	Circuit Parts Set TCR-45 (¥ 47,500) Circuit Parts Set TCR-A7 (¥ 41,500) CR Part Set CR-3700P (¥ 7,500) Push-Pull Tube Panel VP-1 (¥ 2,000) Push-Pull Tube Panel VP-2 (¥ 2,000) Tube Panel for Single VP-3 (¥ 2,000) Unprocessed Tube Panel VP-4 (¥ 1,500) Output Transformer OY15-3.6K-HP (¥ 12,800) Output Transformer OY15-5K-HP (¥ 12,800) Output Transformer OY15-2.5K-HS (¥ 12,800) Output Transformer OY15-3.5K-HS (¥ 12,800)

Self-made tube panel

VP-1
Push-Pull Tube Panel

Hole for GT Pipe -4
Hole for MT Pipe -4

VP-2
Push-Pull Tube Panel

Hole for GT Pipe -4
Hole for MT Pipe -4

VP-3
Tube panel for single

Hole for GT Pipe -2
Hole for MT Pipe -3

VP-4

There is no hole for the tube socket. Please select a vacuum tube and process it freely. However, the gap between the tube wall of the output tube and the output transformer should be at least 40 mm.

Holes for MT Pipes <VP-1 ~ VP-3>	Holes for GT Pipes <VP-1, VP-2>	Hole for GT Pipe and ST Pipe <VP-3>

Usable Tube Socket (All for 9P) SATO (S-7250, S-482) QQQ(S9-241Y) SMK(S-B7712)	Usable Tube Socket (SB-801, S-B2603 for 12P, others for 8P) SATO (S-3898, S-501US) QQQ (S8-401C, SB-801) SMK (S-B3406, S-B2603)	Usable Tube Socket In addition to the GT tube tusocket that can be used in VP-1 and VP-2 SATO (S-501VX, S-501UY, S-501UT) can be used

Power transformer 9F380 using A3700

Primary Applications	Full load input	Core stack thickness	Weight	Price
8045G, KT-88, 6CA7-Push-Pull Stereo 8045G, KT-88, 6CA7, 2A3 - Single stereo	320W	68mm	6.5kg	¥15,800

Terminal array

Connection method

This power transformer provides voltages of 720 V / 190 mA DC, 360 V / 380 mA DC, 295 V / 380 mA DC and 250 V / 380 mA DC by connecting B-windings in parallel or series.

Choke coil 4705 using A3700

Outline	Inductance	Superimposed DC value	DC resistance	Safety current value max	Weight	Price
Type 14	5H(1.25H)	170mA(340mA)	75 Ω (19 Ω)	300mA(600mA)	1.44kg	¥4,400

* The above inductance value is the value when 10V/60Hz is added and specified DC is superimposed. Deviation is within ± 10%. Safety current value is the limit value of DC current that can be continuously supplied.
* In the standard, the standard value outside the parentheses is the value for series connection, and the value inside the parentheses is the parallel connection value.

Connection method

New OY15 output transformer

Model number	Primary impedance	Primary Applications (With SG Tap)	Recommended Capacity	Primary inductance			Allowable DC value		Insertion loss	Weight	Price
Model number	Primary impedance	Primary Applications (With SG Tap)	Recommended Capacity	1V(60Hz)	10V(60Hz)	max	Unbalance	Equilibrium	Insertion loss	Weight	Price
OY15-3.6K-HP	3.6k Ω	8045G, KT-88 For Push-Pull	50W	60H	150H	370H	2.8mA	195mA	-0.4dB	2.4kg	¥12,800
OY15-5K-HP	5k Ω	6CA7, 50CA10 For Push-Pull	50W	80H	200H	510H	2.3mA	160mA	-0.45dB	2.4kg	¥12,800
OY15-2.5K-HS	2.5k Ω	2A3, 8045G, 6CA7 (UL) 6L6GC (UL), 6GB8 (UL) For Single	25W	-	15H	-	120mA	-	-0.57dB	2.4kg	¥12,800
OY15-3.5K-HS	3.5k Ω	2A3, KT-88 (UL), PX-4 6CA7(UL) For Single	25W	-	21H	-	120mA	-	-0.54dB	2.4kg	¥12,800