Re: [Drakelist] R-4A PTO, Act III
All the ones I have seen are points up and down--diamond style. This provides both lateral and vertical support for the rod. Curt KU8L Steve Wedge wrote: Now I'll get a little too granular: should I orient it with a corner on the bottom, or let it ride on the edge of the square? Thanks, Curt, Garey and Gary for all your help so far! Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. -- From: "Curt Nixon" Sent: Monday, July 18, 2011 7:11 PM To: "Steve Wedge" Cc: "Gary Poland" ; ; Subject: Re: [Drakelist] R-4A PTO, Act III Hi Steve: I'm not sure it doesn't matter if the end pc is flush or not but keep it perpendicular to the core axis. You may just have found the culprit there. I like Ambroid cement but nearly anything will work as an adhesive there. A small amount of 5 min epoxy or even some carpenters glue. Curt KU8L Steve Wedge wrote: I thought it would be something of that nature. I have taken the PTO apart enough to slide the coil form off the slug and at least initially I don't see any cracks or loose segments. However, the diamond-shaped washer at the end of the coil came out easily as if it wasn't glued at all. It was flush with the end of the form, but I see that it could be recessed in the brown sleeve so that it is against the white coil form. Does the washer/spacer need to be flush, or bedded down against the form? I'm going to supper shortly, so won't get to look at the slug under my microscope until the table is cleared Winking smile emoticon I have pics if needed. I'm going to clean the whole thing with IPA. Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. *From:* Gary Poland <mailto:gpola...@cinci.rr.com> *Sent:* Monday, July 18, 2011 6:10 PM *To:* Steve Wedge <mailto:w1es1...@earthlink.net> *Cc:* drakelist@zerobeat.net <mailto:drakelist@zerobeat.net> *Subject:* Re: [Drakelist] R-4A PTO, Act III Steve, The T-4X puts a –30 volts on the INJ line when the XMTR position is selected. That –30 shuts down the R-4A’s premixer V8. In RCVR position the –30 volts is removed, the T-4X’s PTO output is deselected, and the R-4A’s injection is then free to be boss. 73, Gary ___ 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] R-4A PTO, Act III
This may be the "BINGO!" moment. The washer was only held in with friction, and it was riding on the flat. Off to do some gluing, I am... Thanks & stay tuned! Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. -- From: "Gary Poland" Sent: Monday, July 18, 2011 9:07 PM To: "Steve Wedge" Subject: Re: [Drakelist] R-4A PTO, Act III Steve , It needs to be oriented in a diamond shape. The brass end shaft rides in the " V ", not the flat. 73, Gary http://home.roadrunner.com/~w8pu ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Now I'll get a little too granular: should I orient it with a corner on the bottom, or let it ride on the edge of the square? Thanks, Curt, Garey and Gary for all your help so far! Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. -- From: "Curt Nixon" Sent: Monday, July 18, 2011 7:11 PM To: "Steve Wedge" Cc: "Gary Poland" ; ; Subject: Re: [Drakelist] R-4A PTO, Act III Hi Steve: I'm not sure it doesn't matter if the end pc is flush or not but keep it perpendicular to the core axis. You may just have found the culprit there. I like Ambroid cement but nearly anything will work as an adhesive there. A small amount of 5 min epoxy or even some carpenters glue. Curt KU8L Steve Wedge wrote: I thought it would be something of that nature. I have taken the PTO apart enough to slide the coil form off the slug and at least initially I don't see any cracks or loose segments. However, the diamond-shaped washer at the end of the coil came out easily as if it wasn't glued at all. It was flush with the end of the form, but I see that it could be recessed in the brown sleeve so that it is against the white coil form. Does the washer/spacer need to be flush, or bedded down against the form? I'm going to supper shortly, so won't get to look at the slug under my microscope until the table is cleared Winking smile emoticon I have pics if needed. I'm going to clean the whole thing with IPA. Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. *From:* Gary Poland <mailto:gpola...@cinci.rr.com> *Sent:* Monday, July 18, 2011 6:10 PM *To:* Steve Wedge <mailto:w1es1...@earthlink.net> *Cc:* drakelist@zerobeat.net <mailto:drakelist@zerobeat.net> *Subject:* Re: [Drakelist] R-4A PTO, Act III Steve, The T-4X puts a –30 volts on the INJ line when the XMTR position is selected. That –30 shuts down the R-4A’s premixer V8. In RCVR position the –30 volts is removed, the T-4X’s PTO output is deselected, and the R-4A’s injection is then free to be boss. 73, Gary ___ 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] R-4A PTO, Act III
Hi Steve: I'm not sure it doesn't matter if the end pc is flush or not but keep it perpendicular to the core axis. You may just have found the culprit there. I like Ambroid cement but nearly anything will work as an adhesive there. A small amount of 5 min epoxy or even some carpenters glue. Curt KU8L Steve Wedge wrote: I thought it would be something of that nature. I have taken the PTO apart enough to slide the coil form off the slug and at least initially I don't see any cracks or loose segments. However, the diamond-shaped washer at the end of the coil came out easily as if it wasn't glued at all. It was flush with the end of the form, but I see that it could be recessed in the brown sleeve so that it is against the white coil form. Does the washer/spacer need to be flush, or bedded down against the form? I'm going to supper shortly, so won't get to look at the slug under my microscope until the table is cleared Winking smile emoticon I have pics if needed. I'm going to clean the whole thing with IPA. Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. *From:* Gary Poland <mailto:gpola...@cinci.rr.com> *Sent:* Monday, July 18, 2011 6:10 PM *To:* Steve Wedge <mailto:w1es1...@earthlink.net> *Cc:* drakelist@zerobeat.net <mailto:drakelist@zerobeat.net> *Subject:* Re: [Drakelist] R-4A PTO, Act III Steve, The T-4X puts a –30 volts on the INJ line when the XMTR position is selected. That –30 shuts down the R-4A’s premixer V8. In RCVR position the –30 volts is removed, the T-4X’s PTO output is deselected, and the R-4A’s injection is then free to be boss. 73, Gary ___ 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] R-4A PTO, Act III
I thought it would be something of that nature. I have taken the PTO apart enough to slide the coil form off the slug and at least initially I don't see any cracks or loose segments. However, the diamond-shaped washer at the end of the coil came out easily as if it wasn't glued at all. It was flush with the end of the form, but I see that it could be recessed in the brown sleeve so that it is against the white coil form. Does the washer/spacer need to be flush, or bedded down against the form? I'm going to supper shortly, so won't get to look at the slug under my microscope until the table is cleared I have pics if needed. I'm going to clean the whole thing with IPA. Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto. From: Gary Poland Sent: Monday, July 18, 2011 6:10 PM To: Steve Wedge Cc: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Steve, The T-4X puts a –30 volts on the INJ line when the XMTR position is selected. That –30 shuts down the R-4A’s premixer V8. In RCVR position the –30 volts is removed, the T-4X’s PTO output is deselected, and the R-4A’s injection is then free to be boss. 73, Gary<>___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Steve, The T-4X puts a –30 volts on the INJ line when the XMTR position is selected. That –30 shuts down the R-4A’s premixer V8. In RCVR position the –30 volts is removed, the T-4X’s PTO output is deselected, and the R-4A’s injection is then free to be boss. 73, Gary___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Eddy - Sorry to hear of your dissatisfaction with Drake performance! :-) We ALL have those 'moments'.. Drake built better than 100,000 of this basic PTO over the years, so I guess it stands to reason that there might be a 'dog' or two in there... I've 'handled' several hundred of those over the last 40+ years, and haven't seen one yet that couldn't be fixed. As for the 751A, check back with me when one of those custom ICs dies. :-) 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 Eddy Swynar wrote: Hi Steve, The frequency of my T-4X PTO jumps upward almost exactly 100-KHz with the cover removed... I've tried several different "tricks" in futile efforts at trying to tame mine, including (A) unplugging the cooling fan that I added to allow everything inside to "heat soak" properly in the confines of my cool basement (no change), and, (B) "gasketing" the seam at the base of the PTO shield can with aluminum foil to better shield its contents, and to negate any effect that expansion/contraction of the shield might have upon the frequency (again, no effect). I have yet to re-enter the inner sanctum of my PTO here (far too busy with other stuff), but when I do I plan to completely swab everything down inside it that moves with isopropyl rubbing alcohol& Q-tips. The frequency flutter is so very vexing for me that I'm afraid it's fast-removing the gleam in my eye that I've heretofore reserved for Drake gear---indeed, I'm almost ashamed to admit that I'm coming to more& more appreciate the sheer joy& pleasure of the reliability& quality of signal that my old Icom 751A affords me in my portable work, as compared to the on-going grief given me thus far by the Drake Twins. That's sacrilege, I know, admitting such on a Drake Reflector, but it is, alas, a sad reality& fact... ~73~ de Eddy VE3CUI - VE3XZ *** On 2011-07-18, at 12:13 PM, Steve Wedge wrote: Logging on from work: Garey, I thought about that last night and, as luck would have it, I had an extra good 6HS6, which I swapped. There was no change. The PTO seems to be a bit better with the cover removed, not the entire unit. Of course the frequency of the PTO changes considerably with the cover off. It's got me scratching my head, as there should really be no significant heat being generated in there... W1ES Date: Mon, 18 Jul 2011 10:11:15 -0400 From: Garey Barrell To: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Message-ID:<4e243f03.1090...@mindspring.com> Content-Type: text/plain; charset=windows-1252; format=flowed Steve - This has been 'one of those' problems! Just a quick question I've forgotten if you said the PTO was stable outside the radio? IF so have you subbed the PreMixer tube? Possible load change on the PTO due to a tube anomaly? 73, Garey - K4OAH Glen Allen, VA ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Eddy, I don't think aluminum foil makes good gasketing material for two reasons. At least in this country, the shiny side of the foil is coated with Mylar which is nonconducting. In addition, aluminum oxide is an insulator as well. 73, Bob AD3K -Original Message- From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of Eddy Swynar Sent: Monday, July 18, 2011 12:27 PM To: Steve Wedge Cc: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Hi Steve, The frequency of my T-4X PTO jumps upward almost exactly 100-KHz with the cover removed... I've tried several different "tricks" in futile efforts at trying to tame mine, including (A) unplugging the cooling fan that I added to allow everything inside to "heat soak" properly in the confines of my cool basement (no change), and, (B) "gasketing" the seam at the base of the PTO shield can with aluminum foil to better shield its contents, and to negate any effect that expansion/contraction of the shield might have upon the frequency (again, no effect). I have yet to re-enter the inner sanctum of my PTO here (far too busy with other stuff), but when I do I plan to completely swab everything down inside it that moves with isopropyl rubbing alcohol & Q-tips. The frequency flutter is so very vexing for me that I'm afraid it's fast-removing the gleam in my eye that I've heretofore reserved for Drake gear---indeed, I'm almost ashamed to admit that I'm coming to more & more appreciate the sheer joy & pleasure of the reliability & quality of signal that my old Icom 751A affords me in my portable work, as compared to the on-going grief given me thus far by the Drake Twins. That's sacrilege, I know, admitting such on a Drake Reflector, but it is, alas, a sad reality & fact... ~73~ de Eddy VE3CUI - VE3XZ *** On 2011-07-18, at 12:13 PM, Steve Wedge wrote: > Logging on from work: > > Garey, I thought about that last night and, as luck would have it, I had an extra good 6HS6, which I swapped. There was no change. > > The PTO seems to be a bit better with the cover removed, not the entire unit. Of course the frequency of the PTO changes considerably with the cover off. It's got me scratching my head, as there should really be no significant heat being generated in there... > > W1ES > > Date: Mon, 18 Jul 2011 10:11:15 -0400 > From: Garey Barrell > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] R-4A PTO, Act III > Message-ID: <4e243f03.1090...@mindspring.com> > Content-Type: text/plain; charset=windows-1252; format=flowed > > Steve - > > This has been 'one of those' problems! Just a quick question I've forgotten if you said the PTO > was stable outside the radio? IF so have you subbed the PreMixer tube? Possible load change on the > PTO due to a tube anomaly? > > 73, Garey - K4OAH > Glen Allen, VA > > > > ___ > 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 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Hi Steve, The frequency of my T-4X PTO jumps upward almost exactly 100-KHz with the cover removed... I've tried several different "tricks" in futile efforts at trying to tame mine, including (A) unplugging the cooling fan that I added to allow everything inside to "heat soak" properly in the confines of my cool basement (no change), and, (B) "gasketing" the seam at the base of the PTO shield can with aluminum foil to better shield its contents, and to negate any effect that expansion/contraction of the shield might have upon the frequency (again, no effect). I have yet to re-enter the inner sanctum of my PTO here (far too busy with other stuff), but when I do I plan to completely swab everything down inside it that moves with isopropyl rubbing alcohol & Q-tips. The frequency flutter is so very vexing for me that I'm afraid it's fast-removing the gleam in my eye that I've heretofore reserved for Drake gear---indeed, I'm almost ashamed to admit that I'm coming to more & more appreciate the sheer joy & pleasure of the reliability & quality of signal that my old Icom 751A affords me in my portable work, as compared to the on-going grief given me thus far by the Drake Twins. That's sacrilege, I know, admitting such on a Drake Reflector, but it is, alas, a sad reality & fact... ~73~ de Eddy VE3CUI - VE3XZ *** On 2011-07-18, at 12:13 PM, Steve Wedge wrote: > Logging on from work: > > Garey, I thought about that last night and, as luck would have it, I had an > extra good 6HS6, which I swapped. There was no change. > > The PTO seems to be a bit better with the cover removed, not the entire unit. > Of course the frequency of the PTO changes considerably with the cover off. > It's got me scratching my head, as there should really be no significant heat > being generated in there... > > W1ES > > Date: Mon, 18 Jul 2011 10:11:15 -0400 > From: Garey Barrell > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] R-4A PTO, Act III > Message-ID: <4e243f03.1090...@mindspring.com> > Content-Type: text/plain; charset=windows-1252; format=flowed > > Steve - > > This has been 'one of those' problems! Just a quick question I've > forgotten if you said the PTO > was stable outside the radio? IF so have you subbed the PreMixer tube? > Possible load change on the > PTO due to a tube anomaly? > > 73, Garey - K4OAH > Glen Allen, VA > > > > ___ > 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] R-4A PTO, Act III
Logging on from work: Garey, I thought about that last night and, as luck would have it, I had an extra good 6HS6, which I swapped. There was no change. The PTO seems to be a bit better with the cover removed, not the entire unit. Of course the frequency of the PTO changes considerably with the cover off. It's got me scratching my head, as there should really be no significant heat being generated in there... W1ES Date: Mon, 18 Jul 2011 10:11:15 -0400 From: Garey Barrell To: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Message-ID: <4e243f03.1090...@mindspring.com> Content-Type: text/plain; charset=windows-1252; format=flowed Steve - This has been 'one of those' problems! Just a quick question I've forgotten if you said the PTO was stable outside the radio? IF so have you subbed the PreMixer tube? Possible load change on the PTO due to a tube anomaly? 73, Garey - K4OAH Glen Allen, VA ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Steve - This has been 'one of those' problems! Just a quick question I've forgotten if you said the PTO was stable outside the radio? IF so have you subbed the PreMixer tube? Possible load change on the PTO due to a tube anomaly? 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 Steve Wedge wrote: I may take you up on this. First, a few observations that I made tonight: 1. Voltage at the +DC supply terminal on the small board under the PTO was 9.18 V. As the frequency jumped around, this voltage did not change. I am accustomed to nominal voltages in older tube gear being "not exact", so being off by 8% didn't seem to be a matter of concern. 2. Waveform on a 100 MHz scope looked good but there was a slight amount of jitter visible at 50 nS/div. 3. Interesting observation: waveform on the premixer side of L6 had some modulation on it that looked like the twists you'd see in loose rope. I'm assuming this is a little bit of cross-mod from the band oscillator. 4. Signals sound less "pure" (almost chirpy) when using the R-4A to control frequency. This occurs on all bands. Everything sounds great when using the T-4X to control the frequency. The T-4X has none of the problems with changing frequency when wiggling the tuning knob. The R-4A is very sensitive to all mechanical inputs. I'm also straining my eyes on this schematic and trying to figure out how the INJ works. I think it's the output from the premixer, V8, which is the difference between the PTO and the crystal band oscillator. How does the receiver "know" which signal (transmitter or receiver) to pick? I'm assuming there's a DC voltage on the INJ line as well as the RF signal (sorry, my eyes were crossing following the switching in the T-4X schematic). 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! - Original Message - *From:* Gary Poland <mailto:gpola...@cinci.rr.com> *To:* Steve Wedge <mailto:w1es1...@earthlink.net> *Sent:* Sunday, July 17, 2011 7:06 PM *Subject:* Re: [Drakelist] R-4A PTO, Act III Steve, Except for a few PTO’s that had no output, I have not had the problems you mention with any Drakes I have owned or serviced over the years. Some that where heavily oxidized or had rusted frames I installed a piece of solder braid like the TR-7’s have. Maybe once in a while the shield would be loose and I would have to “ rework” the spring clips to make them grab better. Except for cleaning and relubing the bearings and worm shaft they just don’t seem to have problems. I have quite a few PTO parts here recovered from the Drake plant when they gave up repair service and a few complete PTO’s that had issues also from Drake. Anyway I would love the challenge if you want to send it this way and of course you would get it back. It’s too bad eBay has run the prices up so high on vintage radio gear and parts. 73, Gary ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Hi Steve: Slug rod and yoke follower can be removed completely by removing the colil form and base from rear of frame and then is-assembling the lead screw. Takes a little fiddling to get the rod then out of the frame but it will fit. Just for inspection, you can just remove the coil form off the back of the frame. Gary might have some more tricks but this has worked for me. The several pcs of core material are sandwiched with a nut and well varnished..never saw one damaged or cracked in perhaps a couple dozen teardowns, but it could happen. Unless they are just loose, I doubt this is doing what you describe. But, anything that might cause mechanical movement in any direction, will cause a frequency shift. Make sure the rear coil form cap with the square hole for the rod is still firmly cemented in place. I always add a little Ambroid cement to the glued parts since the original can get brittle and fail. THe back rod guide is critical to stability of the rod. Curt KU8L Steve Wedge wrote: Date: Sun, 17 Jul 2011 16:00:22 -0400 OK - this is starting to make a little more sense. If the ferrite is cracked or loose, this sort of thing can happen, then, right? What's the best way of extracting the slug from the coil form? Thanks for all the help... Steve, W1ES/4 From: Garey Barrell To: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Message-ID: <4e233f56.7010...@mindspring.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Steve - The chrome rider bar and follower should be clean, with NO lubrication. Ensure that the spring is pulling the follower FIRMLY against the bar. Examine the slug closely for any cracks or loose segments. 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 ___ 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
[Drakelist] R-4A PTO, Act III
Date: Sun, 17 Jul 2011 16:00:22 -0400 OK - this is starting to make a little more sense. If the ferrite is cracked or loose, this sort of thing can happen, then, right? What's the best way of extracting the slug from the coil form? Thanks for all the help... Steve, W1ES/4 From: Garey Barrell To: drakelist@zerobeat.net Subject: Re: [Drakelist] R-4A PTO, Act III Message-ID: <4e233f56.7010...@mindspring.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Steve - The chrome rider bar and follower should be clean, with NO lubrication. Ensure that the spring is pulling the follower FIRMLY against the bar. Examine the slug closely for any cracks or loose segments. 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 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
I may take you up on this. First, a few observations that I made tonight: 1. Voltage at the +DC supply terminal on the small board under the PTO was 9.18 V. As the frequency jumped around, this voltage did not change. I am accustomed to nominal voltages in older tube gear being "not exact", so being off by 8% didn't seem to be a matter of concern. 2. Waveform on a 100 MHz scope looked good but there was a slight amount of jitter visible at 50 nS/div. 3. Interesting observation: waveform on the premixer side of L6 had some modulation on it that looked like the twists you'd see in loose rope. I'm assuming this is a little bit of cross-mod from the band oscillator. 4. Signals sound less "pure" (almost chirpy) when using the R-4A to control frequency. This occurs on all bands. Everything sounds great when using the T-4X to control the frequency. The T-4X has none of the problems with changing frequency when wiggling the tuning knob. The R-4A is very sensitive to all mechanical inputs. I'm also straining my eyes on this schematic and trying to figure out how the INJ works. I think it's the output from the premixer, V8, which is the difference between the PTO and the crystal band oscillator. How does the receiver "know" which signal (transmitter or receiver) to pick? I'm assuming there's a DC voltage on the INJ line as well as the RF signal (sorry, my eyes were crossing following the switching in the T-4X schematic). 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! - Original Message - From: Gary Poland To: Steve Wedge Sent: Sunday, July 17, 2011 7:06 PM Subject: Re: [Drakelist] R-4A PTO, Act III Steve, Except for a few PTO’s that had no output, I have not had the problems you mention with any Drakes I have owned or serviced over the years. Some that where heavily oxidized or had rusted frames I installed a piece of solder braid like the TR-7’s have. Maybe once in a while the shield would be loose and I would have to “ rework” the spring clips to make them grab better. Except for cleaning and relubing the bearings and worm shaft they just don’t seem to have problems. I have quite a few PTO parts here recovered from the Drake plant when they gave up repair service and a few complete PTO’s that had issues also from Drake. Anyway I would love the challenge if you want to send it this way and of course you would get it back. It’s too bad eBay has run the prices up so high on vintage radio gear and parts. 73, Gary___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Gang, Donnie WA9TGT is back making parts for Drakes again, here is the URL .. http://www.2bradioparts.com/ 73, Gary W8PU___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Steve - The chrome rider bar and follower should be clean, with NO lubrication. Ensure that the spring is pulling the follower FIRMLY against the bar. Examine the slug closely for any cracks or loose segments. 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 Steve Wedge wrote: Thanks, Curt & Al. That's what I thought - there would be no logical reason why someone would make that fork loose. I can't help but think that my problem is mechanically-induced. I guess I'm going to have to take the whole bloomin' thing apart so I can clean off the slug. Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! - Original Message - From: "Al Parker" To: "Steve Wedge" Cc: Sent: Sunday, July 17, 2011 1:01 PM Subject: Re: [Drakelist] R-4A PTO, Act III Hi Steve, To answer one question, at least, Yes, the fork is loose purposely. The spring that attaches to it and leads back across the top of the case towards the "outside" keeps it tight against the shaft to that side. The shaft should be smooth. If the spring isn't there you get backlash. 73, Al, W8UT www.boatanchors.org www.hammarlund.info "There is nothing -- absolutely nothing -- half so much worth doing as simply messing about in boats" Ratty, to Mole On 7/17/2011 12:51 PM, Steve Wedge wrote: I'm going to start this with a request for a working 4-twins PTO if anyone would like to sell one to me. I'm wondering, though, as I tightened up the end-screw of the main tuning shaft, if the guide-fork that rides along the upper shaft is supposed to be really loose or not. The frequency jumping definitely occurs if I touch any of these parts - this may be just coincidental. The one thing that makes it so I'm not convinced that it's simple expansion during heating is that the frequency jumps up /and down./ The PTO on my T-4X is nowhere near as sensitive to touching. Looks like I just missed a PTO that went up on eBay at the end of June. Drat. I'm dreading taking this thing completely apart for fear that I'll completely break it. 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A PTO, Act III
Thanks, Curt & Al. That's what I thought - there would be no logical reason why someone would make that fork loose. I can't help but think that my problem is mechanically-induced. I guess I'm going to have to take the whole bloomin' thing apart so I can clean off the slug. Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! - Original Message - From: "Al Parker" To: "Steve Wedge" Cc: Sent: Sunday, July 17, 2011 1:01 PM Subject: Re: [Drakelist] R-4A PTO, Act III Hi Steve, To answer one question, at least, Yes, the fork is loose purposely. The spring that attaches to it and leads back across the top of the case towards the "outside" keeps it tight against the shaft to that side. The shaft should be smooth. If the spring isn't there you get backlash. 73, Al, W8UT www.boatanchors.org www.hammarlund.info "There is nothing -- absolutely nothing -- half so much worth doing as simply messing about in boats" Ratty, to Mole On 7/17/2011 12:51 PM, Steve Wedge wrote: I'm going to start this with a request for a working 4-twins PTO if anyone would like to sell one to me. I'm wondering, though, as I tightened up the end-screw of the main tuning shaft, if the guide-fork that rides along the upper shaft is supposed to be really loose or not. The frequency jumping definitely occurs if I touch any of these parts - this may be just coincidental. The one thing that makes it so I'm not convinced that it's simple expansion during heating is that the frequency jumps up /and down./ The PTO on my T-4X is nowhere near as sensitive to touching. Looks like I just missed a PTO that went up on eBay at the end of June. Drat. I'm dreading taking this thing completely apart for fear that I'll completely break it. 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! ___ 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] R-4A PTO, Act III
Hi Steve, To answer one question, at least, Yes, the fork is loose purposely. The spring that attaches to it and leads back across the top of the case towards the "outside" keeps it tight against the shaft to that side. The shaft should be smooth. If the spring isn't there you get backlash. 73, Al, W8UT www.boatanchors.org www.hammarlund.info "There is nothing -- absolutely nothing -- half so much worth doing as simply messing about in boats" Ratty, to Mole On 7/17/2011 12:51 PM, Steve Wedge wrote: I'm going to start this with a request for a working 4-twins PTO if anyone would like to sell one to me. I'm wondering, though, as I tightened up the end-screw of the main tuning shaft, if the guide-fork that rides along the upper shaft is supposed to be really loose or not. The frequency jumping definitely occurs if I touch any of these parts - this may be just coincidental. The one thing that makes it so I'm not convinced that it's simple expansion during heating is that the frequency jumps up /and down./ The PTO on my T-4X is nowhere near as sensitive to touching. Looks like I just missed a PTO that went up on eBay at the end of June. Drat. I'm dreading taking this thing completely apart for fear that I'll completely break it. 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! ___ 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] R-4A PTO, Act III
Hi Again Steve: There is quite a large amount of clearance in the slotted follower over the rod. It generally stays up against one side due to the spring tension applied with the external spring. Spring is there isn't it? Looks kind of cheesy but works fine. Curt KU8L Steve Wedge wrote: I'm going to start this with a request for a working 4-twins PTO if anyone would like to sell one to me. I'm wondering, though, as I tightened up the end-screw of the main tuning shaft, if the guide-fork that rides along the upper shaft is supposed to be really loose or not. The frequency jumping definitely occurs if I touch any of these parts - this may be just coincidental. The one thing that makes it so I'm not convinced that it's simple expansion during heating is that the frequency jumps up /and down./ The PTO on my T-4X is nowhere near as sensitive to touching. Looks like I just missed a PTO that went up on eBay at the end of June. Drat. I'm dreading taking this thing completely apart for fear that I'll completely break it. 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! ___ 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
[Drakelist] R-4A PTO, Act III
I'm going to start this with a request for a working 4-twins PTO if anyone would like to sell one to me. I'm wondering, though, as I tightened up the end-screw of the main tuning shaft, if the guide-fork that rides along the upper shaft is supposed to be really loose or not. The frequency jumping definitely occurs if I touch any of these parts - this may be just coincidental. The one thing that makes it so I'm not convinced that it's simple expansion during heating is that the frequency jumps up and down. The PTO on my T-4X is nowhere near as sensitive to touching. Looks like I just missed a PTO that went up on eBay at the end of June. Drat. I'm dreading taking this thing completely apart for fear that I'll completely break it. 73, Steve Wedge, W1ES/4 "I can't complain, but sometimes I still do." - Joe Walsh If the above message appears, it came from Steve's Son of Laptop!___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
