[BUILD] fripholm's TG1 Zener Limiter boards - support thread

[fripholm]

Making progress!

I am waiting on push button switches and a fancy IEC inlet. I have everything else.

Thanks!

Paul

Very nice progress. Looking great!

Keep us posted how those meters work in the circuit.

 

[Potato Cakes]

For the Bypass illuminated push button switches, how did you go about wiring your LEDs? I normally take the unused side of the switch and route the VDC from there to the + side of the LED, but for this bypass it is using both sides of the switch. Is it safe to incorporate the VDC with the audio or do need need blocking capacitors? Or do something else?

Thanks!

Paul

 

[fripholm]

For the Bypass illuminated push button switches, how did you go about wiring your LEDs? I normally take the unused side of the switch and route the VDC from there to the + side of the LED, but for this bypass it is using both sides of the switch. Is it safe to incorporate the VDC with the audio or do need need blocking capacitors? Or do something else?

Thanks!

Paul

On my stereo build I have used one side of the switch for the LED and the other to trigger a relay which is used for bypass. Both are getting the +28 volts directly from the PSU. I'm using 24V relays and >10k resistors for the LEDs - the switches are the same ones from don audio, that you are using.

The mono desktop unit just has a simple 2PDT toggle switch, that directly switches BYPASS in or out (no LED). Under some circumstances I'm getting a loud thump when the switch is toggled. It might be a good idea to use a make-before-break switch to avoid this, but I haven't found one.

 

[Potato Cakes]

Yes, of course, a relay! I did something like this on another build but I guess I completely forgot about it. Sorry for the silly question.

Thanks!

Paul

 

[Potato Cakes]

Here's more pics of progress...

Wiring explosion!

 

[Potato Cakes]

Another one

 

[Potato Cakes]

Starting to look like something now.

I thought I had all the parts but it turns out that I don't have the right power transformer or IEC panel mount inlet. All the 2x30V transformers I've found on mouser are made by Hammond and are 80VA, costing around $60 each. Has anybody found a suitable Triad product for this build?

I was hoping to at least power it up before I headed out of town, but now it will be two weeks before that happens.

Thanks!

Paul

 

[fripholm]

Has anybody found a suitable Triad product for this build?

The Triad VPT30-1670 might work.

Looking good! 

 

[Potato Cakes]

It looks like that is 2x15 (30V secondaries in series). That's the one I originally bought.

I'll keep looking.

Thanks!

Paul

 

[fripholm]

It looks like that is 2x15 (30V secondaries in series).

Ooops, you're right.

**nevermind** 8)

 

[JCN1218]

Hey everybody. My build is going along well, boards are populated and my enclosure is all put together. Just waiting on all my transformers at the moment. While I'm waiting for them, I was looking over the schematic and I'm just wondering what kind of grounding scheme to go for. Are there any points on the boards that should be connected to star ground for example, or is the grounding taken care of with the other off board connections.
Also, I'm unsure how to socket the trimmers during the calibration steps. What should I do with the wiper leg? I can't tell from the pic in the build guide.

I'll post some pics of my progress soon. Thanks again to everyone for being so helpful!

 

[Potato Cakes]

Wiper has to in one socket and then either of the other legs in another. Extend by soldering trimmed lead pieces from resistors if needed. Just make sure you measure the resistance on the legs that where in the sockets when calculating permanent values.

For grounding, I use Ian Thompson's Grounding 101 for any and all builds that I do and they always turn out very quiet if the rest of the build is correct. Do a search for it and read it.

Thanks!

Paul

 

[JCN1218]

Awesome! Thanks for the tip. I'll be sure to check it out while I wait for my transformers to get in.

 

[JCN1218]

So far, my build seems to be going very well, so I figured I post up some progress pics.

Here's the back of the front panel. It's almost fully wired up with the exception of the auto-release switches and hold pots. Thanks again to ToBSn for the nifty side-chain boards.

Here's the inside of the case as of now. Power supply isn't installed yet due to lack of power transformer. I have it in a really shallow 3U case with the boards stacked on top of each other. The reason being that my GSSL has a big bolt sticking out the bottom of its case about 6" from the front panel, so I can't rack it above anything that has a case deeper than about 6". I figured this was good opportunity to make something that could live under my GSSL. I'm going to be mounting my input and output transformers on the outside like an LA2A  since I have limited space inside the box.

Here's the front panel with all the goodies on it. I actually don't have the meters properly mounted yet, I was hoping they'd come with mounting hardware but I had to order some after the fact. Should be getting here tomorrow. This is my first custom front panel from Front Panels Express and I'm really happy with how it turned out. It definitely has the biggest cool-factor of anything in my rack so far. I'll be leaving it there until I get the transformers in, at which point I can work on it more. Power trafo should get in this week, the audio ones I ended up ordering from Sowter so I could mount them externally. They haven't even shipped yet, so it might be a while before I can start testing. Calibrating this beast, especially with the stacked boards, is certainly going to be a fun challenge.

 

[ToBSn]

Hey guys,

very cool. Good work! 

I´m currently working on my front panel design...
Not finished yet, just a good start to experiment.  ;D

 

[TwentyTrees]

LOVE that design - sleek! Those toggle switches work really well, is there a link you can share?

Hey guys,

very cool. Good work! 

I´m currently working on my front panel design...
Not finished yet, just a good start to experiment.  ;D

 

[Potato Cakes]

Just so people are aware, you can get DC mA versions of the retro style Sifam meters that are sold by Don Audio:

https://sites.google.com/site/diypartsstore/catalog/pcb-transistors-op-amps-pots

The catch is you have to buy their TG boards with the purchase. I still haven't been able to order the correct power transformer to power up my build and work on getting the VU version I have to track correctly. So if there are some people waiting for those results to determine if they want to go this metering route, you might want to consider the DC mA version.

I've order somethings before from them in the past and I didn't have any issues.

Thanks!

Paul

 

[innercityman]

Yeah, I visited their page when searching infos on the TG1 and I wondered what's the difference between their TG1 kit and Fripholm's one ?

 

[JCN1218]

Concerning the illuminated push button bypass wiring. I saw in an earlier post something about using a relay to trigger the bypass and wiring the led to one side of the switch. I've never worked with relays before. If anyone would be willing to explain that setup a little more in detail or perhaps post a crude wiring diagram it would be highly appreciated.

 

[Potato Cakes]

Relay is a basically a switch activated by power. One side of the push button is going to send power to the relay (make sure it's rated for the VDC you are using) and the relay switches the two things you need on/off (LED power, bypass, what ever you decide). You can do some searches for relays in a GSSL and it should give you an idea, although some of those images have been taken down.

Thanks!

Paul