New Revibe project

[sluckey]

OK, so on your layout, is the LED cathode the black wire or is it the yellow wire?

It's the black wire. That row of turrets on the top of the board that are all tied together is a ground buss.

[SleepLess]

Mmm... One more question Sluckey: I'm building the wires that connect the tank and the top of the chassis. Do you use the metal shield on them or do you only use the signal wire on them? I don't know if I'm clear...

I turned the unit on and the lamp didn't turn on. I then soldered a wire that connects both lamp tabs and it didn't turn on either... I checked voltages and I have 117VAC on both tabs. Isn't it supposed to lit up with 117V?

I do have good heater voltages on all the tube sockets: 3.38VAC


Mmm... All tubes lit up fine. The LED works too and blinks well. I need to reverse the slow/fast switch because it goes faster on the slow position. That's easy to do.
Maybe my lamp indicator is dead? I will try and plug the effect in my amp tomorrow and check if everything works.

[sluckey]

I'm building the wires that connect the tank and the top of the chassis. Do you use the metal shield on them or do you only use the signal wire on them?

You must use a shielded cable for the reverb tank cables. Connect the shield of the cable to the shell of the RCA phono jack. You can use a stereo patch cable (like for your CD player or turntable) but it won't be purdy.

I checked voltages and I have 117VAC on both tabs. Isn't it supposed to lit up with 117V?

Not if you have the same voltage on BOTH tabs. You need 117v on one tab and zero volts on the other tab. Looking at the Weber diagram for your PT I would guess the indicator lamp should connect between the black and brown primary wires. Measure voltage ACROSS those two wires, not from a wire to chassis. While you're at it, measure voltage between the brown and blue wires. You may be able to use those for your lamp rather than the black and brown wires.

You did not tell me if your lamp is a neon type.

[SleepLess]

OK SLuckey, I modified my previous message just before you posted yours. I'm using shielded wire for the RCA connections. I must use the shield on one end of the cable only, right? Do I use it on the tank end or one the RCA inputs on the chassis?

The lamp I'm using is a Marshall type 115-120V  indicator. I don't think those are neons. I'm gonna try and do what you say!
Thanks!

[SleepLess]

Fixed Sluckey! The lamp now lits up. I connected the brown 120v wire on one of the tabs and a wire on the other tab that goes to the common wire of teh PT hwich is soldered on the mains neutral lug.

I'll report tomorrow for sounds! Have a good night! THANK YOU!

[sluckey]

I'm using shielded wire for the RCA connections. I must use the shield on one end of the cable only, right? Do I use it on the tank end or one the RCA inputs on the chassis?

NO. Connect the shield on both ends of the patch cables.

[SleepLess]

Done Sluckey! Thanks a lot for your help. I have just played with it, it sounds phenomenal. The tremolo is the best I have ever heard. It almost sounds like a Univibe. I love the fact that the Reverb is useful all the way. I love it with all the dials on 6. Usually with a reverb you can't go beyond 4 or it's surf heaven, but here it's more subtle and you can really use it even on 10.

THANKS FOR THIS GREAT PROJECT!!!

[sluckey]

Great! Everyone should have a Revibe!   

[bakerlite]

I soldered the 120V PT wire to one tab of the lamp and didn't connect it to the other one.
Thanks!

Just for my own curiosity... you are running this eu voltage right?
so you hook up black and the grey primaries (0v and 240v) and then you get your HT of 260v on the red wires and heaters on the 2 greens ; centretapped green/yellow.


thats fine - but is what you are saying that you are going to try and use a 120v primary to power the led?


i always thought primaries= "power in" to transformer - secondaries = "power out"


sorry if its a silly question but how does this work??

[SleepLess]

I soldered the 120V PT wire to one tab of the lamp and didn't connect it to the other one.
Thanks!

Just for my own curiosity... you are running this eu voltage right?
so you hook up black and the grey primaries (0v and 240v) and then you get your HT of 260v on the red wires and heaters on the 2 greens ; centretapped green/yellow.


thats fine - but is what you are saying that you are going to try and use a 120v primary to power the led?

No the indicator lamp is fed with 120V, not the LED.

i always thought primaries= "power in" to transformer - secondaries = "power out"


sorry if its a silly question but how does this work??

Well, the EU PT has 240v, 220V, 120V and 0V wires. So actually all of these wires give that out. The indicator needs 120V so I soldered the 120V wire there and linked it with the 0V wire as well.

I'm not sure I understand your question... 

[sluckey]

i always thought primaries= "power in" to transformer - secondaries = "power out"

And that's 'usually' how most of us think. But not always the case.       For example, take a simple 120V(primary) to 6.3V (secondary) filament transformer. If you put 120v in you get 6.3V out. ***BUT*** If you apply 6.3V to the secondary you will get 120V out of the primary. The transformer don't care about secondary or primary labels. The labels are for us.

Take a look at the attached drawing for the specific PT that Sleepless is using. And for a moment just ignore where the input voltage is applied. The primary winding has several taps. If you measure 240V between the black and grey wires, you will also measure 220V between the black and blue wires, and you will measure 120V between the black and brown wires.

It's the same operation as a 6.3V winding that has a center tap. You measure 6.3V across the whole winding, or you measure 3.15V across either outer wire and the center tap wire.

Hope this helps.

[bakerlite]

oooh cool - I missed that reply. thanks


That actually makes perfect sense.


Fantastic Build by the way!

[SleepLess]

Hi there!
I thought I'd get back to my topic after a bit more than a year of using the Revibe to ask for some tips on mods for two things:
1. I now think that even the slow tremolo position is too fast, how can I reduce the tremolo speed even more? What components should I change and for what values?
2. It seems that my revibe is quite noisy. That noise is greatly amplified by the amp. This is the cable I used to connect the reverb tank input and output with RCA jacks, could it be the culprit? What would you do? And if change it, for what wire (reference?)



Thanks a lot! ASide from that, I'm still really diggging it, it's fabulous!

[PRR]

> slow tremolo position is too fast

There is a series-string of caps in the oscillator. Double all of them.

Actually: tack same-value caps across the existing caps, try it. That's "double" without buying more odd caps. If that is too slow, back off to 1.5X values (0.3, 0.15, 0.15) which could be faked by using half-value caps across each original cap.

[SleepLess]

Thanks a lot, I'll try that! Any ideas about the hum?

[Willabe]

Any ideas about the hum?

Need to see good close up pictures. 

[SleepLess]

Hi.
Wow. Sorry for not having replied sooner. It's crazy how time flies when you move and have two kids... Here are the pics. I'll try and modify the resistances soon now to reduce the trem speed.

[SleepLess]

Hi there!
Just to make sure I'm not going to change the wrong caps, these are the three I need to double the values of right?

[sluckey]

correct

[Willabe]

Can you post some pics of the back side/transformer side of the chassis?

[sluckey]

Can you post some pics of the back side/transformer side of the chassis?

Look at page 1 of this thread. The PT is inside the chassis. This is an exact copy of my revibe.

[Willabe]

Ok, but I'd still like to see how the verb tank is mounted. 

[sluckey]

Reply #33 doesn't show what you want to see? Do you mean how is the tank actually attached to the chassis? If so, there are 4 bolts that come up through the chassis. Those 4 bolts pass through rubber grommets in the tank and nuts hold it all together. The rubber grommets provide shock resistance as well as insulation between the tank body and the chassis. The 8Ω input connector is near the cap cans. The sensitive output connector is very near the recovery tube.

[Willabe]

Yes it does. This is an old thread and forgot he has posted them already.

[SleepLess]

NO problem thanks a lot guys! The speed is solved, that is a lot better to me. Now on to the hum...

[traynor]

Here are a few mods I made to my build. I noticed there was quite a bit of tone sucking when going through the unit as opposed to bypassing it entirely. To solve this I increased C29 to 1000pf (this brought back all the low end) and R24 to 22K for unity gain. This gave me the same tone when by-passed. The 1000pf may change the trem slightly but I haven't noticed a diff and I have it on a switch in case I find it does on some settings. I suggest that everyone should bypass their unit to make sure there is no loss of tone. Maybe it was just my build.
Brent