Klemt Echolette S

[notea]

Thanks Oc disorder,

-I got this values from ECC82: pin 3 = 989 ohms, pin 8 = 2k20, pin 2 = 1Mohms, pin 7 = 1Mohms (this is strange we expected to have 100k..)

-good thing is i measured 1k14 for the 3 record heads

We're making good progress here!

Cheers Nick

[oc disorder]

Hmm...
Pins 3 & 8 should be joined together and not have different readings 989Ω -220kΩ ???????
Double check the pins again pin numbering clockwise from above .
The 1 meg readings from pins 2 & 7 are consistent ! I would expect them to be different if the two 100k's had gone high.
Try reversing the meter probes and measure again.

Maybe some residual DC is affecting your multimeter readings.

If the 470/500Ω cathode resistor is open circuit it would explain the fault.

I haven't measured around the ECC82/12AT7. It's very hard to get to. Perhaps the osc. coil could be carefully removed to gain
access to the ECC82/12AT7 tube/valve base and then placed back?

I'm glad the heads are ok.

[notea]

Hi,
sorry i did the readings anti-clockwise, corresponding to the number written under the socket.
- So clockwise we've got Pin 3 = 995k ohms, Pin 8 = 996k ohms, Pin 2 = 2k18, Pin 7 = 989 ohms

- i checked the voltage on Pin 8 and we've got 22V DC, nothing on Pin 3, Pin 4 is 224V DC and Pin 9 is 196V DC
Pin 1 and 6 is zero..

Hope i did good..

[oc disorder]

Hello again
It still seems to me the readings are not right . If you look at the diagram pin 3 and pin 8 are joined.
You get a reading of 995k ohms on 3 , more or less identical on 8 996K ohms (contact resistance) which shows
(if they are the right pins) they are connected but you only measure 22volts DC on pin 8 and not on pin 3.
Those readings if correct show the resistor has gone "high" nearly 1 megohm .It should be 470 ohms... I would put a 1 watt there.
Pin 4 and 9 (and 5) are the heater or filament connections. The 12 in 12AT7 shows it can run on 12 volts however they provide a centretap at pin 9 which allows the two "halves" to be in parallel and run on 6.3 volts. Pins 4 & 5 are joined together and 6.3v AC
is applied to pin 9 and (4+5). For practice you should be able to measure that pins 4 and 5 are joined and between that and pin 9 there is approx 6.3v AC.
Pins 1 and 6 are the anodes and the high voltage (H.T.) should be there.
After we solve the measuring system I would get right into the base of that tube/valve and find the actual resistors and measure them. I think you will have to remove or move the coil to gain access ..make sure you label or name the wires so it can go back to where it lives !! Do you have another ECC82/12AT7 ? We may need one later if this one is no good.

[notea]

Hi,

first i want to apologize cause the tube was not at his right place, i measured the n°4..
Sorry about that and thanks Oc Disorder for your patience, as well as for this schematic very usefull.

So i measured the good one this time and we have:

- Pin1= 0V DC, Pin3= 100 k + OV DC, Pin5 = 5V AC, Pin6= 0V DC, Pin8 = 100K + 0V DC

-On pin 4 and 9 my multimeter is going mad, oscillating between 600 and over 1000 V AC!

- i checked the Nachhall reverb button behind the front panel and i've got the 300 V needed.

Do you think C19-C20-C21 are shorted?

Thanks again,

cheers Nick

[oc disorder]

That's good !
"Do you think C19-C20-C21 are shorted?"

Not yet.. :-) but I think the 300v is not getting to the osc coil
and the 470 ohm is also bad at pins 3 & 8 ... 100k is too high
we would expect that on pins 2 or 7.

On the above diagram post #79 "bias-osc-klempt-Echolette.jpg"
on the left is a 470 ohm resistor going from the switch to a capacitor
1uF 350v and then goes to the center tap of the osc. coil.
I forgot to label these components.

On the osc. coil bakelite "tag strip" are all it's connections.

One of them is the power in (probably about 295volts DC).

Although the tube is not oscillating at the moment the D.C. supply
to the coil should be there.
One of the terminals should measure nearly 300 volts DC.
I'm not sure which is which ??? but with the multimeter
set to DC volts you should be able to find the DC between one
of the terminals and ground.

If not we may have another faulty 470 ohm , this time between the
switch and the coil.

Please be careful with the high voltages , if you suddenly stop posting we may get worried !!

[notea]

Hello Oc,

i made it, i feel lucky to write this post

i 've got the 300 VDC (actually oscillating slowly between 300-310 V but i guess it's normal),

i'll be away from the echolette and be back on tuesday, then i'll look for this 470 ohms resistor

cheers Nick

[notea]

Hi Oc,

I'm back to this beast, and i did the reading anti-clockwise this time of the ECC82, and it's seems that we've got the proper values here except that there is no DC at pin3&8.

Pin 1= 300V, Pin2= 100K, Pin3= 470 ohms+ 0 DC, Pin 4&5= 5V AC, Pin6 = 305V, Pin7= 100K, Pin8= 470 ohms+ 0 DC, Pin9= 0 AC

can't explain why there is no DC at pin 3&8?

Cheers, Nick

[notea]

sorry you gave me the answer at #73..

If there is no DC at pin3&8 of the Ecc82 it's because of the osc coil that doesnt' work properly.
-So i checked the lug of the 0.1 uf cap and there is no voltage at all,
-so no voltage on L2 and 300 VDC on L1, that's mean the cap is dead right?
- i don't know where the test point is on the osc coil for the 270V AC so i checked each lug and i got nothing except where there is the DC coming (i read 600-650 AC)

thanks Nick

[oc disorder]

Hi again Notea
I am having trouble reaching the "last post" on this thread so will start a new thread
shortly called "Klemp Echolettes...(cont.)".

In the meantime some suggested French links to capacitors
| Farnell element14

http://fr.rs-online.com/web/c/?sra=o...EUR+200pF+500v

and some related entertainment:-

Further reading on things that flip back and forth (oscillator)
https://www.youtube.com/watch?v=WkipSDmoOHU

Astable Multivibrator (Oscillator)

C U soon !

[Mickey]

Hi Nick, a bit off the beaten track but the photo of the bottom of the motor indicates to me that the end retaining plate is missing. If this is the case you will damage the motor when turned on.
There is usually a plate that is held by screws which screw into the four holes that you can see in your picture and this plate keeps a ball bearing in place on which the motor shaft rests.
Did you remove it?
Cheers, Mie

[Mickey]

Hi Nick, to measure the heads unsolder them carefully (one at a time) where they connect to the level adjustment variable capacitors which are located on the LHS just near the motor. They should read about 1k ohms, actually you don't have to unsolder tham as they are in series with the variable capacitors.

[Mickey]

Have you measured the heads? This can be done without unsoldering by just measuring across the leads to the heads where they come from the variable adjustable capacitors.These are on the LHS just near the motor and each head should read about 1K ohms. Cheers, Mike

[oc disorder]

Mickey .. In post #75 Nick measured the record heads at just over 1k.
I think there are two types of Motor .. if you look closely at Nicks photo you can see a circlip and it appears there is a nylon cover on the bottom of the motor shaft.
The other type of motor has different ventilation slots. And... he has measured a healthy 300 volts going to the coil
and on both anode connections.
I put some fuzzy pics of Kazoomans motors for comparison beside Nicks which happen to be the same type.

[pfrost89]

Greetings! I just received my Echolette NG51 S, which I bought on eBay from Germany. It seems that I'm in luck! The unit sounds like the demos I have heard on YouTube, and all the knobs are reacting to my turning on them. I need a new tape though. I easily changed the old powerport to a new IEC-connector, fired it up and tried to record my vocals. I used a DIN y-cable to split the dry and wet signal, so I can blend it in when I'm producing my vocals later on.

Three small problems with my unit:
1) The light behind the on/off and reverb knobs has gone out.
2) The tape motor is also making quite a bit of noise, especially when I choose the fast reverb mode.
It will bleed into the recording if I stand too close.
3) The rubber mounts that holds the two tubes on the left is dissolving.
How can I fix this? Thanks in advance!

You can hear a quick test here. My chain: Shure 545 > Echolette (fast setting - I increase towards the end) > Soundcard.
I have then gated, EQ'ed and compressed both signals. I'm quite happy with the result and it bodes well for future use!

https://soundcloud.com/bigskycountry...altake/s-nG86A