Testing a completed 18 Watts Amp

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Bieworm
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Re: Testing a completed 18 Watts Amp

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"THIS should be played at high volume..preferably in a residential area"

ViperDoc
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Re: Testing a completed 18 Watts Amp

Post by ViperDoc »

Here's the one I use. I use 40 watt bulbs.

https://ampgarage.com/forum/viewtopic.p ... 545d4f546d

EDIT: And here's the latest version:

https://ampgarage.com/forum/viewtopic.php?f=6&t=34311
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Re: Testing a completed 18 Watts Amp

Post by TriodeLuvr »

davemojo wrote:
Sat 03/27/21 3:36 am
Hey All,

so I guess I could actually use that isn't?

https://www.ebay.co.uk/itm/Packs-of-Inf ... SwaEhZFWhG

I already prepared the bulb light current limiter
Something like this would be my choice; very easy to see if it's beginning to light up:

https://www.barkerphotographic.ie/no-1- ... o-lighting

Incidentally, when testing an amp for the first time that has a tube rectifier, I always substitute a solid state plug-in for the first run with a variac. The tube rectifier can surprise you when it suddenly reaches the threshold where it begins to deliver current. I would do the same thing with a limiter, just to be sure B+ isn't dependent on the rectifier filament being at full power.

Jack
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Re: Testing a completed 18 Watts Amp

Post by davemojo »

Hey All,

So with few bucks I was finally able to get a 250W 230v bulb light a double outlet some cable with power-cord plug and the bulb plate holder.

I have a piece of square wood like plywood and ready to go next week since I order everything online since here you can't just walk in to a shop and buy what you need , no yet bloody pandemic is limiting freedom... :cry:
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Re: Testing a completed 18 Watts Amp

Post by davemojo »

Here some results

I have connected the bulb light current limiter between the wall receptacle and the Amp.
I put the amp standby switch on and the amp main switch off.
I plugged the amp power cord into the bulb limiter and the bulb light limiter to the wall receptacle, it is actually a lead extention that goes into the wall.

I then at this point kept amp standby switch on and turned on the amp, the amp indicator light turns on but the bulb light didn't go on at all no even for a sec, so either I built the bulb light limiter wrong or something else isn't right. However the amp didn't smell any burned or smoked or anything like that.

The light on the amp was lit red but i switched all of after about 10 secs

The current seems to be flowing to the amp since the amp light is lit, unsure what's wrong with bulb limiter.

In the Netherlands the power cord cable are made with 2 colors brown and blue + ground yellow/green

On the limiter I didn't use any ground I have connected the brown cable from power cord plug to the bulb light holder took another piece of brown that goes from the other side of the connector straight to the outlet where the amp will be connected

The blue cable instead runs directly to the outlet and doesn't engage on the bulb light holder,

Hope my explanation is clear, see photo

Thanks
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Re: Testing a completed 18 Watts Amp

Post by Bieworm »

When the light bulb limiter lights up there is a short inside the amp, if it doesn't light up the amp is probably all right... that's IF the light buld limiter is built ok. You can test the limiter by creating a short. Simply by putting a jumper wire between the blue and the brown wire. If the bulb lights up it's working.
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