Weber Copper Cap Rectifiers

Please be sure to read the FAQ.

Weber Copper Cap Rectifiers are solid state rectifier replacement devices for use in place of vintage tube rectifiers. Each model emulates the forward conduction resistance curve of the tube type it replaces and also has linear in-rush current limiting to simulate the warm-up of a tube rectifier, however, it is in the 1 to 2 second range, rather than the 7 to 9 seconds of a typical rectifier tube. The envelopes are solid hard-drawn copper with a high thermal capacitance that allows a 100% continuous overload condition.

The Copper Cap emulates a tube rectifier, but it does not require filament power. In the case of a 5U4, for instance, this is a savings of 15 watts. The power transformer will run cooler and last longer. While the filament and coating on the cathode of a tube rectifier are destined to eventual failure, a Copper Cap will last the lifetime of the amp when used properly. Additionally, close tolerance parts are used in all Copper Cap models; no hand sorting is necessary.

To install an octal, 7, or 9 pin Copper Cap rectifier, simply remove the existing rectifier and replace it with the Copper Cap. Make sure the tube rectifier is cooled down before you remove it.

Installation of the Module Type Copper Cap Rectifier requires knowledge of high voltage power supplies and the precautions of working with potentially lethal voltages. We do not recommend the installation of our module type Copper Cap Rectifiers unless the customer is skilled in those areas. To wire in a module type Copper Cap rectifier requires an understanding of the high voltage supply in your particular amp. In the case of a full wave rectifier supply, simply connect the two orange wires from the Copper Cap module to the high voltage winding from the power transformer. Next, find the point where the full wave diodes connect to a wire that feeds the high voltage to the filter capacitors and the rest of the B+ circuit. Disconnect that wire from the two diodes and connect it to the red wire from the Copper Cap module. It is not necessary to remove the original diodes from the circuit.

For the bridge type Copper Cap module, connect the orange wires to the high voltage winding wires coming from the power transformer. Connect the red wire from the Copper Cap module to the wire in the circuit going to the filters and B+ circuit. Connect the black wire from the Copper Cap module to a convenient power ground point. It is not necessary to remove the bridge diodes from the circuit, but you must disconnect the wire feeding the B+ circuit from the diodes so it can be connected to the red wire from the Copper Cap module.
Picture of Copper Cap Module mounted in amp

Model	Replaces	Imax	Vdrop @ Imax	Price
WA2	OA2	30ma	148V Regulator	$22
WAL5	6AL5	9ma	2V Max.	$12
WX4	6X4/EZ90	70ma	22V	$22
WX5	6X5	70ma	22V	$22
WAV4	6AV4/EZ91	90ma	22V	$22
WZ80	EZ80	90ma	22V	$22
WAX5	6AX5	125ma	50V	$22
WY3GT	5Y3GT	125ma	50V	$22
WCA4	6CA4/EZ81	150ma	28V	$22
WV4	5V4	175ma	25V	$22
WZ34	GZ34/5AR4	225ma	17V	$22
WZ3 4 Pin Base	5Z3	225ma	58V	$27
W83 4 Pin Base	83	225ma	16V	$27
W80 4 Pin Base	80	125ma	60V	$27
WR4	5R4	250ma	67V	$22
WU4GB	5U4GB	275ma	50V	$22
WZ68	2x GZ34/5AR4	450ma	17V	$22
Wx	Custom User Specified	Custom User Specified	User Specified	$22
WS1	Diodes and Limiter only No Sag	1Amp	1V max	$17
WFW	Fullwave circuit with leads Chassis mounted With limiter and GZ34 sag	225ma	17V	$22
WFWx	Fullwave circuit with leads Chassis mounted User Specified	Custom User Specified	User Specified	$22
WBR	Bridge circuit with leads Chassis mounted With limiter and GZ34 sag	225ma	17V	$22

Can I use the C-Caps in an amp that doesn't have a standby switch?
Yes, the inrush current limiting prevents large current surges from occurring.

Are the C-Caps drop-in replacements or do I need to make changes in the wiring?
All octal-based C-Caps are drop-in replacements. Because they don't require filament power, the 5 volt filament source may be either left connected as is or disconnected and used for some other purpose.

How does the C-Cap work?
It is a combination of diodes, power resistors, and other circuitry that emulate the warm-up and operating curve of the tube type rectifier it replaces.

What about the peak currents that occur when the filters are in the charging cycle?
The combination of the conservative power rating of the C-Cap and the high thermal capacity of the copper envelope prevent any stress problems from transient power pulses, etc. Plus, all C-Cap models are rated for 100% overload.

Do I have to do anything special to use the C-Caps?
The octal-based C-Caps are about twice as heavy as a standard glass-envelope vacuum tube, so you should ensure the tensioning on the rectifier socket in your amp is correct, particularly in the case of Fender amps where the tube hangs upside down. No other precautions need be taken other than to make sure you give it plenty of time to cool down as you would a tube before removing it.

What other C-Caps are you working on?
I am developing an adjustable model that will have a control knob on the top of the C-Cap envelope. It will allow the user to drop the B+ up to a certain amount for experimenting with different B+ values. The idea will work fine in a cathode biased amp (over a practical range), fixed bias outputs will need rebiased when the B+ is changed.

What is a WZ68?
In the case of the model WZ68, it is effectively two GZ34's in parallel to emulate the evolution of a higher current, low forward drop GZ34 had that evolution occurred. The WZ68 will work well in a 4 output tube 100 watt circuit and will yield similar sag and other characteristics as a GZ34 in a 50 watt circuit.

What are the PIV ratings of a C-Cap?
Octal and Module Copper Cap models are rated at 2,000 PIV. 7 and 9 pin Copper Caps are rated at 1,000V PIV.

What is a Wx ?
The Wx is a user customized model. If you know the B+ sag you are looking for at a specific current, we will build to that specification. The values you select are limited by the maximum allowable power dissipation in the Copper Cap, which is 20 watts (10 watts for 7 and 9 pin units). For maximum life, it is preferable to keep the dissipation under 10 watts (5 watts for 7 and 9 pin units). When ordering a custom unit, add a suffix to the base model 'W' that indicates the sag in volts followed by the current in milliamps. Example: W50-200.

Use the calculator below to determine a safe power rating.