The AM Forum
March 28, 2024, 06:48:00 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: my home brew tube tester  (Read 3771 times)
0 Members and 1 Guest are viewing this topic.
PA0NVD
Member

Offline Offline

Posts: 615


Nico and Chappie (Chappie is the dog...)


« on: June 21, 2018, 05:48:39 PM »

I took my tube tester out of the shipping container to Costa Rica. The customs did break the glass of the meter and I am replacing it. And thought to share some pics and information now it is on the table
Tube testers are quite difficult to get in Europe and expensive. In addition, they are in general not suited to test tubes at a bit more power.
So I made my own using the cheap (nice) DVM's from China and all switching power supplies. The general power is supplied by a wide range switcher of 200 Watts from China delivering 32 Volts. From there I use a current boost converter for the filament ranging from 1.2 - 30 Volts at approx 50 Watts max.
The anode and G2 supplies by two home build switchers ranging from 20 - 350 VDc. Anode max 120 Watts, G2 50 Watts
The grid supplies are made by a home brew switcher delivering + / - 100 VDC
All supplies are continuous short-circuit proof without overheating
Every grid has its own small DVM and helipot to adjust the voltage from -100V to +100V (4 grids)
The anode and g2 supplies have also a DVM.
The anode current is measured by an analog meter with 5 ranges, 3 mA, 10 mA, 30 mA 100 mA and 300 mA. This meter has a switch to switch over to G2 current.
The G1 supply can switch a 1 MOhm resistor in series to measure gas or grid emission.
In order to avoid oscillation, all wires to he tube bases have at the end of the connection wire a series C and R to ground to damp the Q of an eventual resonance.
I added also a DVM to measure directly trans conductance. I did this by injecting approx 0.5V block to the grid supply and measure with  a synchronous home build meter circuit the AC current in the anode circuit.
The socket connections are selected  by 8 x 11 position switches and two switches can interconnect every pin with an other.  The central contacts of these switches are, GND, GND, Filament, G1, G2, G3, G4 and Anode
In addition there are 9 x 2 mm sockets to make more interconnections or measuring points and a ground socket.  Every socket is connected to a pin of the tube socket field. So when there is a double triode or so, I can connect he tubes in parallel. There are 2 connections available for top caps at tubes.
Was fun to design and build and the tester did serve me quite well. The trans conductance meter is nice to match tubes
When my shack is ready again, I will test all tubes in my sets. Fun job and keeps me out of the bar  Wink


* tube tester top.JPG (1146.35 KB, 2592x1944 - viewed 352 times.)

* tube tester bottom.JPG (1610.55 KB, 2592x1944 - viewed 386 times.)
Logged
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #1 on: June 22, 2018, 12:39:52 PM »

That's a real fine tester there! Sometimes I wonder if customs is incompetent or just evil. Breaking stuff and no accountability.
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
PA0NVD
Member

Offline Offline

Posts: 615


Nico and Chappie (Chappie is the dog...)


« Reply #2 on: June 22, 2018, 02:10:41 PM »

Customs is a real problem here in Costa Rica. My container was abandoned for a short moment due to paper work errors of the shipping company. That was immediately used by the customs in Limon. They did empty it and went through it like it was a flea market. Many paintings and materials were destroyed, they did rob the inheritance of my father, a flint rifle of 1790, did rob a solar panel, my chainsaw and perhaps more.  And you can't do anything against it. I tried, but it sinks down in paperwork, no responses to mails, falsification of paper work etc. They also made me pay almost 9000 $ due to storage in the abandoned area, wich was not my decision nor my fault.  But fortunately they did not consider my collection of old military and civil radios interesting or perhaps to obvious to rob due to its size and weight. So I still have my radio stuff.They did not repack the container, simply did trow everything in destroying many materials.
Friends of us did buy a 50 inch TV in the us. It arrived in limon, When they recollected it, only the box was there, the TV was gone.
many, many stories like that. Various goods sent from Europe simply don't arrive.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #3 on: June 24, 2018, 08:39:36 PM »

Got to ask, why would you want to live in a place like that?
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WD5JKO
Member

Offline Offline

Posts: 1996


WD5JKO


« Reply #4 on: June 24, 2018, 09:48:52 PM »

Back in the 1980's, there was a good AM ham in Costa Rica. Here in Texas he could be heard on 75m, and 10m. He had a homebrew transmitter. As I recall it had a very "flat" 4-400 in the RF final amplifier. Several stateside AM'ers sent him tubes. I think W1GAC was one who had several 4-400 broadcast pulls that he sent. In every case the tubes were "opened" before the ham got them. By open, I mean with a hammer. Huh

Jim
Wd5JKO
Logged
PA0NVD
Member

Offline Offline

Posts: 615


Nico and Chappie (Chappie is the dog...)


« Reply #5 on: June 24, 2018, 10:48:13 PM »

The next is not a political critisism, it is just an answer at the above questions.
Every country has it pro and contra's. I came from Spain,  the most corrupt country I ever lived in. I will never put a foot in Spain again. Fantastic country to visit, a hell to live in. They even have tax over the sun....
Costa Rica has really many beautiful things. A spectacular nature and wild life, The most reforestation of the whole world. A peace loving country that doesn't even has an army. They did put the money for an army in health care and education. In general very nice and open people, NO stress here, foreigners are welcomed, If you speak Spanish, you integrate in no time and it is very easy to make friends. (about 20% of our village are people from the USA and Canada), you still can buy property and build for very good prices. We really love it and our life changed for the better. The organisation of many things is still not what one sees in Europe and the USA, e.g. customs, post system etc. You can put a lot of weight in that, we don't. I lost VERY much more in Spain due to LEGAL robbery, corruption. But other things are organized very well, starting a business, some tax systems, low cost high quality health care, very good universities etc. If you buy a property that has little or no trees, the government gives you free fruit and other trees to reforest your property. Many, many hectares again have trees due to that program. Costa Rica should be an example for the whole world in this aspect. 96% of the energy is green energy. Older people with low income are given a property and a house.  With the low stress life in this beautiful nature and climate, I am happy to accept these disadvantages, they are outweighted by far by all the advantages.
Where we live, 22 degrees C at night, 28 in daytime, the whole year around. A dry season and a wet season and all is fluorescent green. Monkeys in the trees, jaguars in the forest, many beautiful birds many exotic fruits everywhere. That is Costa Rica
Logged
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #6 on: June 27, 2018, 04:24:10 PM »

Customs is a real problem here in Costa Rica. My container was abandoned for a short moment due to paper work errors of the shipping company. That was immediately used by the customs in Limon. They did empty it and went through it like it was a flea market. Many paintings and materials were destroyed, they did rob the inheritance of my father, a flint rifle of 1790, did rob a solar panel, my chainsaw and perhaps more.  And you can't do anything against it. I tried, but it sinks down in paperwork, no responses to mails, falsification of paper work etc. They also made me pay almost 9000 $ due to storage in the abandoned area, wich was not my decision nor my fault.  But fortunately they did not consider my collection of old military and civil radios interesting or perhaps to obvious to rob due to its size and weight. So I still have my radio stuff.They did not repack the container, simply did trow everything in destroying many materials.
Friends of us did buy a 50 inch TV in the us. It arrived in limon, When they recollected it, only the box was there, the TV was gone.
many, many stories like that. Various goods sent from Europe simply don't arrive.

wow.. as corrupt as the place is.. well, you could probably arrange for the miscreants to be 'punished'. But I suppose it is nice enough once you get past that.
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
PA0NVD
Member

Offline Offline

Posts: 615


Nico and Chappie (Chappie is the dog...)


« Reply #7 on: June 27, 2018, 06:27:34 PM »

Indeed Patrick. I just leave it behind just as I left all the corruption in Spain behind and start living here. We are really very happy now. about 3 - 4 weeks more and our house is ready and we can move in and GET ORGANIZED AGAIN (also the shack!!  Cheesy)
Logged
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #8 on: July 01, 2018, 10:28:32 PM »

One thing you have made me do, by this tale, is to consider always insuring what I ship.
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.039 seconds with 19 queries.