Re: [drakelist] T4B Trouble
Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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] T4B Trouble
Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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] T4B Trouble
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - OK. Those no load voltages are fine. I'd check the rest of the path to the final grids. Perhaps a bad power cable or connector wiring / short? Typical failure scenario you described is that the bias voltage fails, causing the T/R relay to pull in, keying the transmitter (grounding the final cathodes) and with no bias the tubes conduct as much as they or the power supply or the cathode resistors can handle until one or the other opens up. Open cathode resistors are certainly a symptom of extreme overload of the PA tubes. You say the finals were bad. How did you determine that they were bad. I guess I'm stubborn. I still say the bias supply failed, somewhere between the AC line and the PA grids! :-) My next guess is that the Cinch connector(s) have a problem, e.g., short or open of the bias line. Possibly intermittent? 73, Garey - K4OAH Glen Allen, VA Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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] Happy new year
Happy new year to all Only make a few posts but read all of them Was good to hear old friends on 3863 last nite Evan. thank you for taking the Drake net for me.. This is the start of the 14th year of it.. Danny ...WA4SDE
Re: [drakelist] T4B Trouble
Robert Ladden [EMAIL PROTECTED] made an utterance to the drakelist gang -- Did you move things around when you switched rigs? I found (the hard way) that it is possible for the cinch connector to get in an angle where the bias pin loses contact. 73, Bob WW3QB At 12:05 PM 1/1/2008, you wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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] R4-C Filters INRAD vs Original Piezo
Hello Drakelist: Does anyone know how the INRAD selection of 5695 KHz 2nd IF filters for the R4C compare against the original Piezo Technology filters offered by Drake? Would I be better off obtaining original Drake filters or going with the INRADs. regards Wade
Re: [drakelist] T4B Trouble
Jim F. [EMAIL PROTECTED] made an utterance to the drakelist gang -- I see that tube bias is a big problem in these sets. Any chance of fusing the cathode resistors to would help stem the bias problem ? Do you think a couple of cathode wired-in-series fuses work ? Jim --- Bill Carpenter [EMAIL PROTECTED] wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I did move the T4XB to plug/unplug my straight key so that is a possibility. Thanks for the tip and Gary I don't disagree that it was a bias problem. I'll get new resistors and we'll see. - Original Message - From: Robert Ladden [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 12:08 PM Subject: Re: [drakelist] T4B Trouble Robert Ladden [EMAIL PROTECTED] made an utterance to the drakelist gang -- Did you move things around when you switched rigs? I found (the hard way) that it is possible for the cinch connector to get in an angle where the bias pin loses contact. 73, Bob WW3QB At 12:05 PM 1/1/2008, you wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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] T4B Trouble
Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I tested the tubes on my tube tester. I know this is not always conclusive but the meter on the tester did not move at all on either tube. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 11:31 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - OK. Those no load voltages are fine. I'd check the rest of the path to the final grids. Perhaps a bad power cable or connector wiring / short? Typical failure scenario you described is that the bias voltage fails, causing the T/R relay to pull in, keying the transmitter (grounding the final cathodes) and with no bias the tubes conduct as much as they or the power supply or the cathode resistors can handle until one or the other opens up. Open cathode resistors are certainly a symptom of extreme overload of the PA tubes. You say the finals were bad. How did you determine that they were bad. I guess I'm stubborn. I still say the bias supply failed, somewhere between the AC line and the PA grids! :-) My next guess is that the Cinch connector(s) have a problem, e.g., short or open of the bias line. Possibly intermittent? 73, Garey - K4OAH Glen Allen, VA Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was happily CWing away when the Bline kind of blinked so I turned it off. Later I found no output at all so suspecting finals I checked them and yes they were bad. I put good ones in and still no output. There had been no noise, smoke or burned sound so I had not looked under the finals. I did that this morning and found R32 and R33 (1 watt 15 Ohm) both burnt and testing very high or open. Obviously I need to replace these but is there anything else I should check first to see what may have caused this to happen? Any help appreciated. Happy New Year! 73 Bill NZ0T -- Submissions:[EMAIL PROTECTED] 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] R4-C Filters INRAD vs Original Piezo
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Wade - The Drake filters are generally fine, and if you can save some money while getting GOOD Drake filters, they should cost about half of what the Inrad filters cost. The vast majority of the Drake filters still meet their specifications. That said, the Inrads are better filters. They had the benefit of 25 years of technology improvement, and much more powerful computers, resulting in smoother passband among other things. Obviously they are also 25 years younger, and crystals DO age over time. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com wmacleod wrote: Hello Drakelist: Does anyone know how the INRAD selection of 5695 KHz 2^nd IF filters for the R4C compare against the original Piezo Technology filters offered by Drake? Would I be better off obtaining original Drake filters or going with the INRADs. regards Wade -- Submissions:[EMAIL PROTECTED] 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] T4B Trouble
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - OK, just curious. They can fail completely, yet still light. As someone else noted, given just the right set of circumstances it is possible for the bias pin of the Cinch connector to lose contact with its mate while still maintaining Plate, Screen and Filament voltage to the PA. The pins are all identical in length, but Murphy has a lot to do with those sorts of things! :-) The internal connections on the cable connector and the terminals on the chassis side are very close together, and the bias supply is high impedance, so it is possible to short the bias long enough to cause a failure without killing the supply itself. It'll be interesting to know what you find! 73, Garey - K4OAH Glen Allen, VA Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I tested the tubes on my tube tester. I know this is not always conclusive but the meter on the tester did not move at all on either tube. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 11:31 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - OK. Those no load voltages are fine. I'd check the rest of the path to the final grids. Perhaps a bad power cable or connector wiring / short? Typical failure scenario you described is that the bias voltage fails, causing the T/R relay to pull in, keying the transmitter (grounding the final cathodes) and with no bias the tubes conduct as much as they or the power supply or the cathode resistors can handle until one or the other opens up. Open cathode resistors are certainly a symptom of extreme overload of the PA tubes. You say the finals were bad. How did you determine that they were bad. I guess I'm stubborn. I still say the bias supply failed, somewhere between the AC line and the PA grids! :-) My next guess is that the Cinch connector(s) have a problem, e.g., short or open of the bias line. Possibly intermittent? 73, Garey - K4OAH Glen Allen, VA Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Power supply seems OK. Bias adjusts from -49 to -90 and voltages at 279 and 682. Both a little high but seem OK to me. Anything else I should check before I try replacing the cathode resistors? Gotta wait to order some anyway. - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 10:34 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep, that's it. It's adjustable to set the idle current for the finals. No bias voltage = full plate current! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Gary, I'll look at the AC-4 though I replaced the electrolytics a few years ago. Which pin is the bias measured on? It looks like pin 9 to me at -45 to -65 volts against pin 1 which is ground? - Original Message - From: Garey Barrell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, January 01, 2008 9:46 AM Subject: Re: [drakelist] T4B Trouble Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Bill - Sounds like you lost the bias supply in the AC-4, electrolytics and/or rectifiers. There has been some discussion of this over the last few weeks on here. The AC-4R kit from The Heathkit Shop is the best answer for AC-4's that still have their original electrolytics. You got lucky in that the cathode resistors opened! Carbon comp resistors are pretty hard to find. Best replacement is the Ohmite OX ceramic composition resistor available from Mouser and others. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com Bill Carpenter wrote: Bill Carpenter [EMAIL PROTECTED] made an utterance to the drakelist gang -- I was enjoying SKN last night on 40M with my Bline but decided to switch to my K2/100 to use a more effective NB against bad powerline noise that has popped up here recently. I left the Bline on and was
Re: [drakelist] Starting on my TR-3
Gary Poland [EMAIL PROTECTED] made an utterance to the drakelist gang -- Paper towels, cotton swabs, and Windex. 73, Gary W8PU http://home.cinci.rr.com/w8pu -- Submissions:[EMAIL PROTECTED] 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] Starting on my TR-3
john [EMAIL PROTECTED] made an utterance to the drakelist gang -- Yep...leave the steam cleaner for the car... Cotton balls manuvered with some tweezers and Qtips will do a much better job without wrecking things. Yes, I know Tektronix did it, but this isn't Tek gear, and it isn't the 70's anymore. Take your time and enjoy learning what's in your rig as you carefully clean it. You'd be surprised the things you see merely by carefully cleaning your gear the slow and deliberate way. I like lighter fluid on cotton ball swabs (unlit) :-) Enjoy your TR3...it's a really great SSB rig John K5MO At 04:28 PM 1/1/2008, [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] writes: The biggest question I have is how to best clean the chassis. Having now done a TR4 a TR4C Q tips and rubbing alcohol denatured alcohol also works but might lift a marginal tube number decal. Carl Hibbard WD8NHK -- See AOL's http://food.aol.com/top-rated-recipes?NCID=aoltop000304top rated recipes and http://body.aol.com/fitness/winter-exercise?NCID=aoltop000303easy ways to stay in shape for winter. -- Submissions:[EMAIL PROTECTED] 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] R4-C Filters INRAD vs Original Piezo
Garey (OK, I just recently picked up that we have both a Garey and a Gary here, I'm pretty slow :), HOW do the crystals age ? Is it the mechanicals inside or just what ? Chuck, K1OM On Jan 1, 2008 3:52 PM, Garey Barrell [EMAIL PROTECTED] wrote: Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Wade - The Drake filters are generally fine, and if you can save some money while getting GOOD Drake filters, they should cost about half of what the Inrad filters cost. The vast majority of the Drake filters still meet their specifications. That said, the Inrads are better filters. They had the benefit of 25 years of technology improvement, and much more powerful computers, resulting in smoother passband among other things. Obviously they are also 25 years younger, and crystals DO age over time. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com wmacleod wrote: Hello Drakelist: Does anyone know how the INRAD selection of 5695 KHz 2^nd IF filters for the R4C compare against the original Piezo Technology filters offered by Drake? Would I be better off obtaining original Drake filters or going with the INRADs. regards Wade -- Submissions:[EMAIL PROTECTED] 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] RV7 jumping frequency
[EMAIL PROTECTED] made an utterance to the drakelist gang -- As an addendum, I've experienced such problems on several rigs due to a ground connection that was intermittant, going high resistance, etc. **See AOL's top rated recipes (http://food.aol.com/top-rated-recipes?NCID=aoltop000304) -- Submissions:[EMAIL PROTECTED] 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] R4-C Filters INRAD vs Original Piezo
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- You think YOU have problems. I have a very hard time typing Gary!! :-) All crystals change with age. There are many factors, but a few are adsorbing (or releasing) contaminants that were trapped at manufacture, different coefficients of mounting materials, possibly even flaking off particles of quartz, stress relief in mounting structures, and on and on.. Aging is akin to drift, in that both result in the frequency of oscillation changing over time. Like drift, it can go in either direction. Aside from all the handwaving, I think the biggest source is lack of cleanliness in manufacturing. Obviously cleanliness costs money, and the bargain crystal makers seem to cut that expense first. Probably because it doesn't show up for years, and is therefore not their problem. :-) You'll find band crystals in Drake (AND Collins) equipment that are several kHz off frequency after 20 -30 years. Even with the best of manufacturing processes crystals still age, just at a slower rate. Typical aging for quality crystals can still be in the range of 5-10 ppm/year (5 -10 Hz per year) which is plenty good enough for our uses. Anyway, when the 4-8 crystals in a crystal filter start changing frequency at random, all sorts of bad things happen to the passband. Usually excessive ripple in the passband is the first to suffer. Insertion loss goes up (think of multiple IF stages that are tuned to different frequencies rather than all on the same frequency), etc. In severe cases (say a chunk of flux finally breaks off of a crystal element!) a big notch or peak can show up in or outside of the passband 73, Garey - K4OAH Glen Allen, VA Chuck Grandgent wrote: Garey (OK, I just recently picked up that we have both a Garey and a Gary here, I'm pretty slow :), HOW do the crystals age ? Is it the mechanicals inside or just what ? Chuck, K1OM On Jan 1, 2008 3:52 PM, Garey Barrell [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: Garey Barrell [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] made an utterance to the drakelist gang -- Wade - The Drake filters are generally fine, and if you can save some money while getting GOOD Drake filters, they should cost about half of what the Inrad filters cost. The vast majority of the Drake filters still meet their specifications. That said, the Inrads are better filters. They had the benefit of 25 years of technology improvement, and much more powerful computers, resulting in smoother passband among other things. Obviously they are also 25 years younger, and crystals DO age over time. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B C-Line Service Supplement CDs www.k4oah.com http://www.k4oah.com wmacleod wrote: Hello Drakelist: Does anyone know how the INRAD selection of 5695 KHz 2^nd IF filters for the R4C compare against the original Piezo Technology filters offered by Drake? Would I be better off obtaining original Drake filters or going with the INRADs. regards Wade -- Submissions:[EMAIL PROTECTED] 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] Need Soldering tips for Wen 75 soldering pistol
Jim Pruitt [EMAIL PROTECTED] made an utterance to the drakelist gang -- Since QTH lists do not seem to want to let me post this, I wonder if anyone on this list can help me? Does anyone know of a source for soldering tips for a Wen model 75 soldering pistol? It is a 75 watt gun? I am in need of one (or more). I know that Wen discontinued the gun (and I assume the tips too) several years ago. I am working on my R4B and my tip broke. Now I find out that the tips do not seem to be available anywhere. Thank you. Jim Pruitt -- Submissions:[EMAIL PROTECTED] 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] Need Soldering tips for Wen 75 soldering pistol
Dennis Monticelli [EMAIL PROTECTED] made an utterance to the drakelist gang -- I don't know, Jim, but I am also interested in a source for tips because I have a Wen 75 as my backup iron. You may have to find a parts unit. On Jan 1, 2008 9:52 PM, Jim Pruitt [EMAIL PROTECTED] wrote: Jim Pruitt [EMAIL PROTECTED] made an utterance to the drakelist gang -- Since QTH lists do not seem to want to let me post this, I wonder if anyone on this list can help me? Does anyone know of a source for soldering tips for a Wen model 75 soldering pistol? It is a 75 watt gun? I am in need of one (or more). I know that Wen discontinued the gun (and I assume the tips too) several years ago. I am working on my R4B and my tip broke. Now I find out that the tips do not seem to be available anywhere. Thank you. Jim Pruitt -- Submissions:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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 --
