Re: [drakelist] WTB Solid tube solid state tubes for B and C line
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Neil, I have used bright blue LEDs in my R4A. I took out the white reflector and re sprayed it white. I then shone the blue LEDs (two of them) into the quasi parabolic diffuser. Suited me. 73 Kevin VK3DAP / ZL2DAP neil wrote: neil [EMAIL PROTECTED] made an utterance to the drakelist gang -- Jim Pruitt wrote: Jim Pruitt [EMAIL PROTECTED] made an utterance to the drakelist gang -- I am again trying to find some solid tubes. I have seen none advertised on here for quite some time and wonder if anyone has any lying around that they would like to part with for the B or C line. Speaking of which... I've wondered how hard it would be to make some things like this (assuming, for discussion, that you could get some appropriate 7 or 9 pin bases to build on)? Diodes are obvious, and I suppose an FET could be rigged to work as a triode, but how would you replace a more complex (multi-grid) tube? Dual-gate mosfet or some combination of parts? Also - anyone tried using bright blue LEDs instead of bulbs + blue filters for the dial and meter illumination? My filters are shot... Neil KX2Y -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] R7A Available
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Shame, Randy, Shame!! 73 Kevin VK3DAP / ZL2DAP Randy Moore wrote: Randy Moore [EMAIL PROTECTED] made an utterance to the drakelist gang -- I am considering parting with my R7A to help fund my newest hobby, motorcycles/ Anyone interested? I am open to suggestions as to a fair price. Thanks, Randy Moore AI4CO -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
[drakelist] Neutralising T-4X
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Things are moving along smoothly, if slowly, with refreshing an old T-4X. Final tubes have been replaced, screen and anode voltages disconnected at the feed thru capacitors on the wall into the final cage (just lifted the RF chokes and taped up the loose leads). Connected a short coax lead with a PL259 plug into the antenna socket and the other end with bare braid and centre conductor to enable connection to the oscilloscope. Fired up the transmitter and tuned the anode capacitor for a maximum signal on the scope, then tuned the neutralising capacitor for a minimum signal. So far so good. However, this is the first neutralisation I have done in 50 years and I think I need a bit of help, please. Should I have terminated the coax with a 50 ohm carbon resistor where I have attached the scope? There is a mains hum signal on the trace. Is this likely to be caused by an earth loop between the scope connection to mains earth, the AC4 connection to mains earth and the probe earth connected to the T4-X chassis? Should I simply omit connecting the probe earth to the transmitter chassis or the coax braid? Yes I could experiment, but I don't want to risk misaligning the set. 73 and thanks in advance Kevin VK3DAP / ZL2DAP -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] shelf life of tubes
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- I hesitated and Googled to no avail before offering my two cent's worth, but I seem to remember reading recommendations about bringing up the heaters or filaments very, very slowly (i.e. over hours rather than seconds) using a variac, soaking the tubes for several hours at rated voltage or just a tad below before applying voltages to the anode and screen (with suitable bias voltage to the control grid of course). I think that the article I read had a circuit of equipment designed to do all this, and provide metering of electrode currents, but I am blowed if I can find it now. The point made was that the getter in the tube can still be effective in removing gas, unless, of course, the vacuum seal was defective. RF Parts on their website has a paragraph or two on bringing up NOS tubes. 73 Kevin VK3DAP / ZL2DAP Dennis Monticelli wrote: Dennis Monticelli [EMAIL PROTECTED] made an utterance to the drakelist gang -- I think it is a good idea to power up the filaments for a few hours before putting full voltage on a transmitting tube. I had the experience of putting some 20 year old NOS 6146Bs into a TS-820 (800V HV unloaded). For the first two days of approx 2 hrs use each, I had three occurances of brief single-shot HV shorts due to internal tube arcing. The arc only lasted milliseconds but was enough to dim the panel lights. Residual gas builds up over the years. A HV transmitting tube is highly dependent upon a good vacuum. Just a few hours of hot filament is enough to get the residual gas agitated and then captured by a hot getter flashing. After those several 6146 arc events, the tubes settled down and worked just fine. If I had given them some light exercise prior to installation, I'll bet those arcs never would have happened. On 5/5/06, Garey Barrell [EMAIL PROTECTED] wrote: Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Seems like I have seen something about storing transmitting tubes upright to prevent the filament (or other elements) from sagging. Also a recommendation to run with filament power only for several (?) hours after long term storage before applying HV. There WILL be some leakage past the glass-metal pin seals over time, and when the tube is powered up the getter will absorb some gas. I don't think this is much of a problem with small receiving tubes. There are still plenty of two-digit tubes from the 1930's that are running just fine, along with millions of tubes from the 40's - 60's. 73, Garey - K4OAH Atlanta Drake B C-Line Service CDs http://www.k4oah.com [EMAIL PROTECTED] wrote: Im using WW2 vintage JAN tubes in some of my audio equipment and it works great. But, it just depends. Mark W0NCl -Original Message- From: Goss, Ed [EMAIL PROTECTED] To: Gary Poland [EMAIL PROTECTED]; [EMAIL PROTECTED]; drakelist@www.zerobeat.net Sent: Fri, 5 May 2006 09:09:34 -0400 Subject: RE: [drakelist] shelf life of tubes Goss, Ed [EMAIL PROTECTED] mailto:Ed.Goss%40jhuapl.edu made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net [mailto:[EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net%5dOn Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED] mailto:abqcooks%40aol.com; drakelist@www.zerobeat.net mailto:drakelist%40www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes Gary Poland [EMAIL PROTECTED] mailto:gpoland1%40cinci.rr.com made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe
[drakelist] New Panels for 4-line Series.
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Greetings again from Downunder. Can anyone tell me if some third part supplier makes aluminum front panels for the R4-A and T4-X? The panel of the R4-A is scratched and has nasty nicotine stains on it, although the receiver performs well. Many thanks, Kevin VK3DAP / ZL2DAP -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
[drakelist] Removing Meter from R4-A
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Hi guys, This little mechanical puzzle has me beat. Having taken the front panel off the R4-A, how does one get both the meter and its metal holder out from behind the panel? Any enlightenment gratefully received. Have fun at Dayton! 73 Kevin VK3DAP / ZL2DAP -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] TR-4C transmitter troubleshooting
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- I certainly don't have Garey's expertise or long experience, but I did have a similar problem on one of my TX4 transmitters recently. I changed out the PA tubes and the problem disappeared. 73 Kevin VK3DAP / ZL2DAP Garey Barrell wrote: Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Rob - You don't mention anything about keying the transmitter. You have to key the Push-To-Talk (PTT) of the microphone to switch it to transmit to see the idling plate current. You should hear the relay click when it closes. If the final tubes have plate voltage, screen voltage and filament voltage, and the cathodes are returned to the negative pole of those supplies, they WILL draw plate current! The grid voltage is the only thing that keeps them from drawing AMPS of current in the presence of the other voltages. There are two RF chokes in series between the +650VDC supply and the plate caps of the tubes. There is a 15 ohm, 1W resistor in series with each of the final tube cathodes to another RF choke, through the meter shunt resistor, and then through a relay contact to ground. 73, Garey - K4OAH Atlanta Drake B C-Line Service CDs http://www.k4oah.com R. Ton wrote: R. Ton [EMAIL PROTECTED] made an utterance to the drakelist gang -- I'm finally digging into a TR-4C I bought used some time ago. It worked fine when it was shipped here, but I haven't been able to get any power out of the transmitter. It at least oscillates -- I can hear it on a receiver in the same room. Starting at the beginning... The manual says to adjust the bias on the AC-4 so that the plate meter reads .1 amp. This is with the sideband switch counter-clockwise and the xmtr gain all the way down. The meter seems to read about .025 in receive and goes up just a little when the rig is switched to CW. Adjusting the bias has no effect on the plate meter, but it does indeed adjust the bias voltage. Setting it to -60 volts is no problem, but I'm unable to get any real plate current no matter what I do. Any ideas? I haven't done anything to the radio since I got it except spray the switches with Deoxit D5 and replace R45 (2 ohms -- plate meter shunt resistor!!). This resistor was fried in half. What am I in for? Many thanks in advance! 73, Rob (KFØRT) -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] Mike element for Shure 444?
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- One possible way to go is to purchase Heil HC-4 or HC-5 element. I think that you will also need the XT-1 transformer which will match the element impedance to the Hi Z required by the Drake Mic Amplifier - but check whether your transmitter has a high or low impedance input. See http://www.heilsound.com/ I have no connection with Bob Heil or his company apart from being a customer several years ago. 73 Kevin VK3DAP / ZL2DAP Bill Maddock wrote: I recently purchased a TR-4C and shure microphone. The TR-4C worked great after some alignemnt and cleaning of 1 khz shift relay contacts. The rig works great on cw but mike doesn't work - rig keys up but no audio. I am assuming the TR-4C is working properly, so it must be the mike element. Where can I find a mike element replacement? Thanks and 73, Bill N4ZI Atoka, TN Yahoo! Messenger with Voice. http://us.rd.yahoo.com/mail_us/taglines/postman3/*http://us.rd.yahoo.com/evt=39666/*http://beta.messenger.yahoo.com PC-to-Phone calls for ridiculously low rates. -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
[drakelist] WTB: T4-XB 8 Pole Filters
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks to Garey Barrell who pointed out my error, I am actually looking for TWO T4-XB filters, the USB filter and the LSB filter. Many thanks and 73 Kevin VK3DAP / ZL2DAP -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
[drakelist] T4-XB 8 Pole Filter
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- Hi gang, Anyone out there with a T4-XB 8 pole filter they wish to sell? Please contact me off list. Apologies to owner to whom I sent this post in error. Thanks Kevin VK3DAP / ZL2DAP -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
