Solid state tube replacements for the 5R4GT and 6AX5-GT

[ke7trp]

No. I used a halli reciever here for a test. Then my little audio amp. The diodes show an increase in ripple here. Try it out jim.

[Jim, W5JO]

No. I used a halli reciever here for a test. Then my little audio amp. The diodes show an increase in ripple here. Try it out jim.

Been there done that, it always traces back to the test setup not the transmitter unless the transmitter is bad, more than 5% ripple.  Receivers colocated or close will not give you an honest appraisal.

[ke7trp]

We are not talking about any transmitter. We are talking about taking any tube dc supply, measuring ripple with scope.  Removing tube rectifier, inserting ss rectifier, and measuring ripple again.   I used a b+ from a halli reciever and an audio amp i have on my work bench to test.

[ke7trp]

I think the confusion is comming from the fact that I said I used a receiver for testing. What I meant jim was that I used the POWER SUPPLY in the Halli to test.  It was sitting here open so why not.. I measured the ripple,  Swapped the tube for the SS stack, Then tested ripple on the B+.   

I was never using the reciever for listening.

[W4NEQ]

If I understand that you did the test without using a new series R, then that seems right - the series R not only returns the DC back to normal, but also limits the current peaks charging the cap.  Without the R, the silicon diodes will permit more peak current, and you'll see more ripple.

[Knightt150]

Hello: I have now replaced the 5R4 HV and the 6AX5 LV recitifiers plus the 6AL5. I my RANGER II, here is the results, you asked me to post them.

5R4 HV recitifier before the change out 598 Volts on plate of the 6146 after change out to the WEBER solid state replacement was 604 volts. AC was 1.234V AC before and after change out.

6AX5 LV recitifier before the change out on the plate of the 12AX7 was 126 Volts after the change out to the WEBER solid state replacement was 128 Volts. AC was .235 V AC. before and after change out.

I did not check before or after voltages on the 6AL5.

[ke7trp]

Thanks for posting your data.  The copper caps have the R built in so it looks like ripply is not effected.


The plug is that are popular are the 2637s and the FAA aproved solid state plug ins commonly used in collins gear.   Those are what I used here. They do not have any resistor, They are just diodes and add ripple. 

So the moral of the story here is to add more C if you use diodes or R.

C

[Knightt150]

Hello: Again after two days of off and on use of the RANGER II the WEBER SS replacements are working great ( no on air humm reports). I injected a thousand cycles into the mike jack and the modulated wave form looked picture perfect.

These solid state replacements for the 5R4 and the 6AX5 are first quality products, and are direct drop in's for the tubes.

The voltage difference before and after replacement is only 5 to 6 volt's difference.

Thanks for all your help on this.

John W9BFO