Re: [Drakelist] Drake Twins PTO Woes...
Good Day All, Well, I think taht an update may well be in order here, as to the outcome of my ...red-neck hillbilly (apologies to all you mountain-dwelling folk reading this) fix in the matter of improving the shielding of the PTO can in my Drake T-4X transmitter... In a word: it WORKS!!! SO FAR it works, anyway...again to-day I've completed several CQ calls on 40-meters CW, and was engaged in a couple of lengthy rag chews---and there was NONE of the previous intermittent tell-tale frequency jumpiness / intermittent creeping / jiggling... NOTHING. Needless-to-say, I'm very pleased. Keep in mind, however, that my situation here was probably unique from most others: I had repeatedly removed replaced the PTO shield cover here in efforts to track-down what turned-out to be at least one bad solder joint in the tank circuit. No doubt this served to compromise the integrity of the shielding of the can. Additionaly, my station is situated in a very cold basement environment, AND I have a fan extracting air out of the final 2x6JB6A PA cage, which by default, cools the entire inside of the transmitter... The rig's warm-up cycle was far from normal, as a result, I'm sure... Anyway, FWIW guys, don't neglect the critical effect that even the smallest of gap changes in shielding seams can have upon the field of that permeable-tuned tank coil, and by consequence, your transmit frequency. The aluminum strip shielding technique employed here may be far from eye-pleasing, but the benefits of its presence sure are a joy to the ear...! Hi Hi. Here's hoping that my travails may ultimately benefit another(s) in the Drake community... ~73~ de Eddy VE3CUI - VE3XZ - Original Message - From: Diane and Edward Swynar deswy...@xplornet.ca To: drakelist@zerobeat.net Sent: Tuesday, January 11, 2011 5:42 PM Subject: Drake Twins PTO Woes... Good Day All, Well, I took the T-4X off-line here to-day, set it up on the bench with the top cover removed, exposing the PTO can... I pondered the ways means of sealing the small gaps between the base of the can its metal attaching surface, with the intention of eliminating any consequent expansion/contraction effect(s) of the joints upon the oscillator frequency. I settled upon a rather crude, but I think effective, expediency: I simply cut a strip of aluminum cooking foil, and wrapped it around the can base, being sure that there was overlap on the base that supports the ears of the can. I then bridged the strip (on both sides) with masking tape, ensuring good bonding along the length of the strip... It's inelegant, for sure, but achieves its end purpose, I think... I put the transmitter on 40-meters CW, and noted the tell tale frequency creep one time---however, the rig had been on for only 10 minutes, barely enough time to warm up. After about 90 minutes, I made a couple of QSOs, and called CQs, all-the-while monitoring myself on my R-4 receiver... I'm happy to report that ...so far, so good. I'll need more time to evaluate the results of all this, of course, but I'm encouraged. Perhaps the ultimate answer lies in operating the rigs in an environment that's warmer than the 49F that the basement was this afternoon! Hi Hi. Certainly, time will tell...I guess I could always place a small incandescent bulb somewhere inside the T-4X to help speed its heating /reaching operating temperature---but then that effort would be defeated, in large part, by the cooling fan that extracts air from the 2x6JB6A PA cage! (that rascal keeps the whole inside of the rig cool to the touch). ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drake Twins PTO Woes...
Hi Again Everone, ...Just a brief post-script to this thread... Monitoring the T-4X transmit frequency on my R-4 sure has highlighted the fact that load changes on the AC mains have a detrimental effect upon that receiver. Whenever the forced-air electric furnace / heat-pump in the adjoining room would start, the frequency of the R-4 would creep (and no, it wasn't my frequency that was changing, it was the station I was listrening to). A look at the schematic shows no obvious precautions taken with the R-4 to stabilize critical voltages. I wonder if anyone has ever added a VR tube after-the-fact to their R-4 to stabilize things...? And if so, was it worth the effort...? ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drake Twins PTO Woes...
Now..after you have used it some more with no issue, you need to remove the tin-foil to verify that the problem wasn't simply solved by a repeated re-installation of the standard can ! :) Curt Diane and Edward Swynar wrote: Good Day All, Well, I think taht an update may well be in order here, as to the outcome of my ...red-neck hillbilly (apologies to all you mountain-dwelling folk reading this) fix in the matter of improving the shielding of the PTO can in my Drake T-4X transmitter... In a word: it WORKS!!! SO FAR it works, anyway...again to-day I've completed several CQ calls on 40-meters CW, and was engaged in a couple of lengthy rag chews---and there was NONE of the previous intermittent tell-tale frequency jumpiness / intermittent creeping / jiggling... NOTHING. Needless-to-say, I'm very pleased. Keep in mind, however, that my situation here was probably unique from most others: I had repeatedly removed replaced the PTO shield cover here in efforts to track-down what turned-out to be at least one bad solder joint in the tank circuit. No doubt this served to compromise the integrity of the shielding of the can. Additionaly, my station is situated in a very cold basement environment, AND I have a fan extracting air out of the final 2x6JB6A PA cage, which by default, cools the entire inside of the transmitter... The rig's warm-up cycle was far from normal, as a result, I'm sure... Anyway, FWIW guys, don't neglect the critical effect that even the smallest of gap changes in shielding seams can have upon the field of that permeable-tuned tank coil, and by consequence, your transmit frequency. The aluminum strip shielding technique employed here may be far from eye-pleasing, but the benefits of its presence sure are a joy to the ear...! Hi Hi. Here's hoping that my travails may ultimately benefit another(s) in the Drake community... ~73~ de Eddy VE3CUI - VE3XZ - Original Message - From: Diane and Edward Swynar deswy...@xplornet.ca To: drakelist@zerobeat.net Sent: Tuesday, January 11, 2011 5:42 PM Subject: Drake Twins PTO Woes... Good Day All, Well, I took the T-4X off-line here to-day, set it up on the bench with the top cover removed, exposing the PTO can... I pondered the ways means of sealing the small gaps between the base of the can its metal attaching surface, with the intention of eliminating any consequent expansion/contraction effect(s) of the joints upon the oscillator frequency. I settled upon a rather crude, but I think effective, expediency: I simply cut a strip of aluminum cooking foil, and wrapped it around the can base, being sure that there was overlap on the base that supports the ears of the can. I then bridged the strip (on both sides) with masking tape, ensuring good bonding along the length of the strip... It's inelegant, for sure, but achieves its end purpose, I think... I put the transmitter on 40-meters CW, and noted the tell tale frequency creep one time---however, the rig had been on for only 10 minutes, barely enough time to warm up. After about 90 minutes, I made a couple of QSOs, and called CQs, all-the-while monitoring myself on my R-4 receiver... I'm happy to report that ...so far, so good. I'll need more time to evaluate the results of all this, of course, but I'm encouraged. Perhaps the ultimate answer lies in operating the rigs in an environment that's warmer than the 49F that the basement was this afternoon! Hi Hi. Certainly, time will tell...I guess I could always place a small incandescent bulb somewhere inside the T-4X to help speed its heating /reaching operating temperature---but then that effort would be defeated, in large part, by the cooling fan that extracts air from the 2x6JB6A PA cage! (that rascal keeps the whole inside of the rig cool to the touch). ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drake Twins PTO Woes...
Hi Curt, Oh my, but you can be oh so VERY cruel there...! Hi Hi But you're correct, of course: in order to properly verify / ascertain the success of the fix---or, correctly identify the infamous Red X (as it's dubbed in select circles of problem solving)---one needs to be able to turn the problem off, and then turn the problem on again, by repeating the methodology of said fix... But I think I'll pass here, thank-you very much! I am absolutely weary of removing the top enclosure off of the transmitter, wrestling with that can, AD NAUSEAM...time to make a few QSOs, continue monitoring, for now...! :) ~73~ de Eddy VE3CUI - VE3XZ * - Original Message - From: Curt Nixon cptc...@flash.net To: Diane and Edward Swynar deswy...@xplornet.ca Cc: drakelist@zerobeat.net Sent: Thursday, January 13, 2011 1:56 PM Subject: Re: [Drakelist] Drake Twins PTO Woes... Now..after you have used it some more with no issue, you need to remove the tin-foil to verify that the problem wasn't simply solved by a repeated re-installation of the standard can ! :) Curt Diane and Edward Swynar wrote: Good Day All, Well, I think taht an update may well be in order here, as to the outcome of my ...red-neck hillbilly (apologies to all you mountain-dwelling folk reading this) fix in the matter of improving the shielding of the PTO can in my Drake T-4X transmitter... In a word: it WORKS!!! SO FAR it works, anyway...again to-day I've completed several CQ calls on 40-meters CW, and was engaged in a couple of lengthy rag chews---and there was NONE of the previous intermittent tell-tale frequency jumpiness / intermittent creeping / jiggling... NOTHING. Needless-to-say, I'm very pleased. Keep in mind, however, that my situation here was probably unique from most others: I had repeatedly removed replaced the PTO shield cover here in efforts to track-down what turned-out to be at least one bad solder joint in the tank circuit. No doubt this served to compromise the integrity of the shielding of the can. Additionaly, my station is situated in a very cold basement environment, AND I have a fan extracting air out of the final 2x6JB6A PA cage, which by default, cools the entire inside of the transmitter... The rig's warm-up cycle was far from normal, as a result, I'm sure... Anyway, FWIW guys, don't neglect the critical effect that even the smallest of gap changes in shielding seams can have upon the field of that permeable-tuned tank coil, and by consequence, your transmit frequency. The aluminum strip shielding technique employed here may be far from eye-pleasing, but the benefits of its presence sure are a joy to the ear...! Hi Hi. Here's hoping that my travails may ultimately benefit another(s) in the Drake community... ~73~ de Eddy VE3CUI - VE3XZ - Original Message - From: Diane and Edward Swynar deswy...@xplornet.ca To: drakelist@zerobeat.net Sent: Tuesday, January 11, 2011 5:42 PM Subject: Drake Twins PTO Woes... Good Day All, Well, I took the T-4X off-line here to-day, set it up on the bench with the top cover removed, exposing the PTO can... I pondered the ways means of sealing the small gaps between the base of the can its metal attaching surface, with the intention of eliminating any consequent expansion/contraction effect(s) of the joints upon the oscillator frequency. I settled upon a rather crude, but I think effective, expediency: I simply cut a strip of aluminum cooking foil, and wrapped it around the can base, being sure that there was overlap on the base that supports the ears of the can. I then bridged the strip (on both sides) with masking tape, ensuring good bonding along the length of the strip... It's inelegant, for sure, but achieves its end purpose, I think... I put the transmitter on 40-meters CW, and noted the tell tale frequency creep one time---however, the rig had been on for only 10 minutes, barely enough time to warm up. After about 90 minutes, I made a couple of QSOs, and called CQs, all-the-while monitoring myself on my R-4 receiver... I'm happy to report that ...so far, so good. I'll need more time to evaluate the results of all this, of course, but I'm encouraged. Perhaps the ultimate answer lies in operating the rigs in an environment that's warmer than the 49F that the basement was this afternoon! Hi Hi. Certainly, time will tell...I guess I could always place a small incandescent bulb somewhere inside the T-4X to help speed its heating /reaching operating temperature---but then that effort would be defeated, in large part, by the cooling fan that extracts air from the 2x6JB6A PA cage! (that rascal keeps the whole inside of the rig cool to the touch). ~73~ de Eddy VE3CUI - VE3XZ
Re: [Drakelist] Drake Twins PTO Woes...
Of course... Hope it hangs in there. One of these days I hope to catch you on the air and we can have the Drakes talk to each other! I do alot of CW with the SKCC group. Curt KU8L Diane and Edward Swynar wrote: Hi Curt, Oh my, but you can be oh so VERY cruel there...! Hi Hi But you're correct, of course: in order to properly verify / ascertain the success of the fix---or, correctly identify the infamous Red X (as it's dubbed in select circles of problem solving)---one needs to be able to turn the problem off, and then turn the problem on again, by repeating the methodology of said fix... But I think I'll pass here, thank-you very much! I am absolutely weary of removing the top enclosure off of the transmitter, wrestling with that can, AD NAUSEAM...time to make a few QSOs, continue monitoring, for now...! :) ~73~ de Eddy VE3CUI - VE3XZ * - Original Message - From: Curt Nixon cptc...@flash.net To: Diane and Edward Swynar deswy...@xplornet.ca Cc: drakelist@zerobeat.net Sent: Thursday, January 13, 2011 1:56 PM Subject: Re: [Drakelist] Drake Twins PTO Woes... Now..after you have used it some more with no issue, you need to remove the tin-foil to verify that the problem wasn't simply solved by a repeated re-installation of the standard can ! :) Curt Diane and Edward Swynar wrote: Good Day All, Well, I think taht an update may well be in order here, as to the outcome of my ...red-neck hillbilly (apologies to all you mountain-dwelling folk reading this) fix in the matter of improving the shielding of the PTO can in my Drake T-4X transmitter... In a word: it WORKS!!! SO FAR it works, anyway...again to-day I've completed several CQ calls on 40-meters CW, and was engaged in a couple of lengthy rag chews---and there was NONE of the previous intermittent tell-tale frequency jumpiness / intermittent creeping / jiggling... NOTHING. Needless-to-say, I'm very pleased. Keep in mind, however, that my situation here was probably unique from most others: I had repeatedly removed replaced the PTO shield cover here in efforts to track-down what turned-out to be at least one bad solder joint in the tank circuit. No doubt this served to compromise the integrity of the shielding of the can. Additionaly, my station is situated in a very cold basement environment, AND I have a fan extracting air out of the final 2x6JB6A PA cage, which by default, cools the entire inside of the transmitter... The rig's warm-up cycle was far from normal, as a result, I'm sure... Anyway, FWIW guys, don't neglect the critical effect that even the smallest of gap changes in shielding seams can have upon the field of that permeable-tuned tank coil, and by consequence, your transmit frequency. The aluminum strip shielding technique employed here may be far from eye-pleasing, but the benefits of its presence sure are a joy to the ear...! Hi Hi. Here's hoping that my travails may ultimately benefit another(s) in the Drake community... ~73~ de Eddy VE3CUI - VE3XZ - Original Message - From: Diane and Edward Swynar deswy...@xplornet.ca To: drakelist@zerobeat.net Sent: Tuesday, January 11, 2011 5:42 PM Subject: Drake Twins PTO Woes... Good Day All, Well, I took the T-4X off-line here to-day, set it up on the bench with the top cover removed, exposing the PTO can... I pondered the ways means of sealing the small gaps between the base of the can its metal attaching surface, with the intention of eliminating any consequent expansion/contraction effect(s) of the joints upon the oscillator frequency. I settled upon a rather crude, but I think effective, expediency: I simply cut a strip of aluminum cooking foil, and wrapped it around the can base, being sure that there was overlap on the base that supports the ears of the can. I then bridged the strip (on both sides) with masking tape, ensuring good bonding along the length of the strip... It's inelegant, for sure, but achieves its end purpose, I think... I put the transmitter on 40-meters CW, and noted the tell tale frequency creep one time---however, the rig had been on for only 10 minutes, barely enough time to warm up. After about 90 minutes, I made a couple of QSOs, and called CQs, all-the-while monitoring myself on my R-4 receiver... I'm happy to report that ...so far, so good. I'll need more time to evaluate the results of all this, of course, but I'm encouraged. Perhaps the ultimate answer lies in operating the rigs in an environment that's warmer than the 49F that the basement was this afternoon! Hi Hi. Certainly
Re: [Drakelist] Drake Twins PTO Woes...
Hi Eddy - Can't argue with success! Hope it holds By the way, there IS voltage stabilization in the R-4, an 0B2 at V14. This supplies +150 VDC Regulated to the 100 kHz Calibrator, the PTO and the BAND oscillator. When you said that the frequency drifted 'slowly' when the voltage drops and drifts 'quickly' when the voltage comes back up, I was on board with your filament regulation idea as that's the sort of behavior I would expect. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Diane and Edward Swynar wrote: Hi Again Everone, ...Just a brief post-script to this thread... Monitoring the T-4X transmit frequency on my R-4 sure has highlighted the fact that load changes on the AC mains have a detrimental effect upon that receiver. Whenever the forced-air electric furnace / heat-pump in the adjoining room would start, the frequency of the R-4 would creep (and no, it wasn't my frequency that was changing, it was the station I was listrening to). A look at the schematic shows no obvious precautions taken with the R-4 to stabilize critical voltages. I wonder if anyone has ever added a VR tube after-the-fact to their R-4 to stabilize things...? And if so, was it worth the effort...? ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist