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Tubes Asylum Questions about tubes and gear that glows. FAQ |
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Tubes Asylum Questions about tubes and gear that glows. FAQ |
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In Reply to: Sad to report that Chris Haedt died Wednesday... posted by Steve O on January 28, 2005 at 17:32:31:
Read from bottom up. Chris was so through with helpful hints. This is sad indeed.Tubemonger
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Dear Ted and friends,
Thank you so very much for your kind words. It has been a tremendous comfort hearing from all of Chris' "tester" friends.
I'll send your tester out as soon as possible (I'll email when I do so).
Thank you again.
Cheryl
----- Original Message -----
From: tubes
To: Cheryl Haedt
Sent: Thursday, February 03, 2005 5:37 PM
Subject: Re: Hickok 580 Now Complete
Hi Cheryl:
It was both shocking, and very sad to hear about this unfortunate news on the Audio Asylum. We had just exchanged e-mails with Chris on last Monday, and as usual, Chris gave us great and thorough advice. All of us in the tube community drew comfort in knowing that Chris would be there to answer all our questions about Tube Testers, and do a great job fixing these. He was one of a kind and would really be missed.
You must be tied up with more important things. Please, there is no hurry to find or send our tester back (we do have a backup testers). We'd rather you cash the check now, and wait till you are free to take care of less important matters like these.
Please do not hesitate to contact us if we can help in any way, now or later. Our thoughts and prayers are with you at this difficult time.
Kind Regards,
Ted and all of us at;
Tubemonger
www.tubemonger.com
Please also visit our current listings at Audiogon as follows:
http://cgi.audiogon.com/cgi-bin/search2.pl?seller&Tubemonger
----- Original Message -----
From: Cheryl Haedt
To: tubes@tubemonger.com
Sent: Thursday, February 03, 2005 1:58 PM
Subject: Re: Hickok 580 Now Complete
I'm very sorry to inform you that my husband, Chris died last week. I received your check yesterday, but will not cash it until I locate your tester. A dear radio friend of Chris' (Mark Oppat) will be helping me go through his workshop in the next few weeks. I can assure you that Chris kept meticulous records and his shop was always kept in near spotless
condition. Unfortunately, Chris would know exactly where your tester is, while I will need help in finding it.
As soon as possible, I will ship the tester to you. I appreciate your patience and understanding.
Cheryl Haedt----- Original Message -----
From: Cheryl Haedt
To: tubes
Sent: Monday, January 24, 2005 3:05 PM
Subject: Re: Hickok 580 Now Complete
I don't have anything written up about the 580 tester. I did just review the manual and found a couple of items that could use clarification.
(a) The selectors should all be set to the chart positions before the tube is placed in the tester.
(b) Allow the tube to warm up for about one minute and then press the line set button and set to the line mark.
(c) The bias is most accurately set using the meter on the tester. There are two ranges (5 and 50 volts) and make sure you are on the proper range for the bias required. The bias dial will give a rough idea of the voltage. Press the bias button to get the meter to read the actual bias going to the tube and adjust the dial if necessary. Some tubes like the 6922 are tested using a bias resistor connect through the jack under the meter. I made you the adapter to test such tubes.
(d) Now check the tube for leakage by rotating the knob through the positions. The manual covers this--but you will have to decide what level of leakage is acceptable. In general--a tube with leakage of 250K or less is considered shorted and should be discarded--but the meter goes up to 50 megs. Remember that the shorts test needs to be made for all sections of a tube. At any rate--tubes with a leakage of 250K or less should be discarded and no further testing done. You can easily damage the tester by testing a shorted tube for mutual conductance.
(e) I know that it says to use the locking S4 to do the mutual conductance test--but I don't suggest this. If a mistake is made and the 81 fuse bulb lights up you can quickly release the switch. If the switch is locked down something might burn up. So--I suggest using the non-locking S5 to do the mutual conductance test. Hold the button down long enough to get a stable reading--perhaps 10 seconds or so.
(f) The locking S4 button must be using when doing the gas test. S4 must be locked down at the same time that S8 is locked down. Then the meter is adjusted to zero with the Gas Zero adjust knob on the operating panel. The gas/grid current may be read by pressing S9. A good tube will show little upscale movement. Some typical rejection points for gas are in the manual--but here again you will have to set your standards for allowable grid current.
Note: There is a mistake in the gas test instructions. It says to depress the Gm lock button and then reset the line. This is wrong--the line is never set with Gm buttons down--for either the gas test or the mutual conductance test.
(g) I also noted that the setting for the 5AR4 shows a dial setting of "14"--you should use "10" to provide a proper reading. On the 580 they combined the rectifier meter shunt adjustment with the voltage regulator test pot. It works only fairly well. Testers like the 539C don't try to make the VR pot do double duty.
I hope this helps. I really do not think this tester is a good one for a beginner to start out on. I would master it's operation with experienced people and then teach your student. Many areas or tube testing require judgement and experience.
The 9-pin socket saver should be held down with one hand while the tube is inserted or removed. To test tubes with a 10 pin base remove the socket saver.
Chris
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Follow Ups
- last e-mail from Chris - tubemonger 18:54:33 02/03/05 (0)
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