Re: [Drakelist] T4XB No +250V AND blown Filament Fuse
Paul - Make sure that the TRANSCEIVE switch is in SEPARATE and the MODE switch is in SSB. Are you SURE the relay is dropping out? If these are correct, pull V11 out of the socket. A heater-cathode short in this tube will keep the transmitter keyed. Check the relay carefully. It is possible for the Normally Closed contacts to be pressed down far enough to trap the Arm contact between the NC and Normally Open contacts, keeping the receiver On even though the relay is not energized. A 150 ohm resistor at R3 will dissipate about 1.5 - 2W, which will make the resistor quite warm. 2W of heat is 2W of heat, regardless of how big the resistor is! A maximum of 18 VDC ACROSS R3 is within the normal range. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Paul Gerhardt wrote: 100+ watts out but T4 not going fully to standby mode. Idle current is ok same as before but it is still 'idling' with the TR relay in Receive. I can hear 'noise' in the receiver especially with the INJ cable plugged in. Not all the damage has been discovered. Today I did find a short in one of the 'flea bay' tubes between Cathode and the 'middle' screen on pin 7. The R30 68 ohm 1/2 watt resistor is on pin 7 and it opened. The 100 5 Watt resistor in the AC4 opened this has been replaced with an on-hand 150 ohm 5 watt which is still running hot with the tubes in Filament fuse opened and has been replaced with proper fuse Will ck some more voltages tomorrow. -- Paul Gerhardt K3PG http://pgerhardt.blogspot.com QRP ARCI 6674 FP 274 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] DR-7 board re-install to TR-7
Tried to post this yesterday but my attempt was bounced back as spam. Here's my question: After the digital frequency went blank on my TR-7 I pulled the DR-7 board and reseated all the connectors. The single coaxial cable that has to pulled to remove the boardis the center conductor supposed to be soldered in place on the small board it connects to? It did not feel soldered in place when I removed it and the thin blue wire initially. And unfortunately, when I replaced everything the digital display did not come back. Ken - N0VA___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] R-4A, question 2 of 2
Hi all, The 80 meter crystal in my R-4C stopped working so I borrowed the one out of my R-4A. Works fine but now my R-4A needs a crystal. Noticed five holes in the R-4A chassis just in front of the crystals. Might there be trimmers under there that could get that crystal working again? Maybe I could borrow one from my T-4X but I can't find them. Maybe they're under the chassis? Thanks for any ideas. 73, de Howard, WA9RYF___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] R-4A question 1 of 2
First thing's last here: In the R-4a, the tube just in front of the power transformer has very poor connections with its socket. Is there a good method of cleaning the pin holes in the socket? What does that tube do? It's pretty microphonic when I wiggle it just right. Any suggestions, please. 73, de howard WA9RYF___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] T4XB No +250V AND blown Filament Fuse
OK I did some more checks today and this is what I see. With the Transceive in Separate and INJ cable hooked up I can hear the Transmiter VFO in the Receiver and I can still adj the Idle current (although the idle goes up another needle width when the relay closes) I turned it over and tried poking the relay while in receive mode and it did not change. I can hear it switching and seems to be working but in Separate the xmit VFO is 'ON' and I can adj the level in the receiver with the bias adj. I pulled V11 and it did not change. Will check the T/R relay again and make shure someting is not stuck in the contacts. I feel it is almost working but not yet... In Separate should both neon vfo lights be on all the time? I can't remember but now I have the transmitter neon on ALL the time and the rcvr neon goes OFF when I key the mic. In Rcvr AND Xmit Mode either light stays on all the time. Should Both Neons alternate in Separate? Paul - -- Content-Type: text/plain; charset=iso-8859-1 100+ watts out but T4 not going fully to standby mode. Idle current is ok same as before but it is still 'idling' with the TR relay in Receive. I can hear 'noise' in the receiver especially with the INJ cable plugged in. Not all the damage has been discovered. Today I did find a short in one of the 'flea bay' tubes between Cathode and the 'middle' screen on pin 7. The R30 68 ohm 1/2 watt resistor is on pin 7 and it opened. The 100 5 Watt resistor in the AC4 opened this has been replaced with an on-hand 150 ohm 5 watt which is still running hot with the tubes in Filament fuse opened and has been replaced with proper fuse Will ck some more voltages tomorrow. -- Paul Gerhardt K3PG http://pgerhardt.blogspot.com QRP ARCI 6674 FP 274 -- next part -- An HTML attachment was scrubbed... URL: http://mailman.zerobeat.net/pipermail/drakelist/attachments/20100210/e2cb9576/attachment-0001.html Paul - Make sure that the TRANSCEIVE switch is in SEPARATE and the MODE switch is in SSB. Are you SURE the relay is dropping out? If these are correct, pull V11 out of the socket. A heater-cathode short in this tube will keep the transmitter keyed. Check the relay carefully. It is possible for the Normally Closed contacts to be pressed down far enough to trap the Arm contact between the NC and Normally Open contacts, keeping the receiver On even though the relay is not energized. A 150 ohm resistor at R3 will dissipate about 1.5 - 2W, which will make the resistor quite warm. 2W of heat is 2W of heat, regardless of how big the resistor is! A maximum of 18 VDC ACROSS R3 is within the normal range. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Paul Gerhardt wrote: 100+ watts out but T4 not going fully to standby mode. Idle current is ok same as before but it is still 'idling' with the TR relay in Receive. I can hear 'noise' in the receiver especially with the INJ cable plugged in. Not all the damage has been discovered. Today I did find a short in one of the 'flea bay' tubes between Cathode and the 'middle' screen on pin 7. The R30 68 ohm 1/2 watt resistor is on pin 7 and it opened. The 100 5 Watt resistor in the AC4 opened this has been replaced with an on-hand 150 ohm 5 watt which is still running hot with the tubes in Filament fuse opened and has been replaced with proper fuse Will ck some more voltages tomorrow. -- Paul Gerhardt K3PG http://pgerhardt.blogspot.com -- Paul Gerhardt K3PG http://pgerhardt.blogspot.com QRP ARCI 6674 FP 274 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] desolding tool
I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond.___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] T4Xb
Paul - OK. The receiver MUST be in the EXT MUTE, NB or CAL to be muted by the transmitter. If you unplug the MUTE cable at either end, with the receiver in any of those positions, the receiver should mute. There should be NO idle current when the relay is de-energized. If you pull V11 does the idle current drop to zero immediately? If not, then there is a problem with either C60 feedthru or the wire that goes from the METER terminal to the front of the rear section of the TRANSCEIVE switch. Make sure that the METER lugs are not turned where they are shorting to the bracket or chassis. The neon indicator in the T-4XB should be ON in either the SPOT or XMTR position and turn ON when in transmit, OFF in receive. The indicator in the R-4B is always ON when the FUNCTION switch is in ON, and in EXT MUTE, NB or CAL is ON during receive and OFF in transmit. The fact that the transmit light is ON at all times indicates that there IS short on that key line described above, or the relay is NOT breaking contact when de-energized. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Paul Gerhardt wrote: Garey OK I did some more checks today and this is what I see. With the Transceive in Separate and INJ cable hooked up I can hear the Transmiter VFO in the Receiver and I can still adj the Idle current (although the idle goes up another needle width when the relay closes) I turned it over and tried poking the relay while in receive mode and it did not change. I can hear it switching and seems to be working but in Separate the xmit VFO is 'ON' and I can adj the level in the receiver with the bias adj. I pulled V11 and it did not change. Will check the T/R relay again and make shure someting is not stuck in the contacts. I feel it is almost working but not yet... In Separate should both neon vfo lights be on all the time? I can't remember but now I have the transmitter neon on ALL the time and the rcvr neon goes OFF when I key the mic. In Rcvr AND Xmit Mode either light stays on all the time. Should Both Neons alternate in Separate? Paul - Make sure that the TRANSCEIVE switch is in SEPARATE and the MODE switch is in SSB. Are you SURE the relay is dropping out? If these are correct, pull V11 out of the socket. A heater-cathode short in this tube will keep the transmitter keyed. Check the relay carefully. It is possible for the Normally Closed contacts to be pressed down far enough to trap the Arm contact between the NC and Normally Open contacts, keeping the receiver On even though the relay is not energized. A 150 ohm resistor at R3 will dissipate about 1.5 - 2W, which will make the resistor quite warm. 2W of heat is 2W of heat, regardless of how big the resistor is! A maximum of 18 VDC ACROSS R3 is within the normal range. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com http://www.k4oah.com/ -- Paul Gerhardt K3PG http://pgerhardt.blogspot.com QRP ARCI 6674 FP 274 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] desolding tool
Jim - I love my HAKKO 808. I've had it about three years or so, and it's hard to beat for PC board work. I still use a GC Solder Aid, pointed probe on one end and slotted pin probe on the other that solder will not stick to, two or three sizes of Soder-Wik braid, and two sizes of Solda-Pult spring vacuum desoldering tool. The HAKKO is terrific for desoldering thru-hole component leads, while the braid works better on surface mount, sometimes with the aid of a piece of #30 enameled wire, and the solder aid and spring vacuum desolderer is best for tube gear. All work well at what they do best. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Jim Wagner wrote: I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] DR-7 board re-install to TR-7
It is not supposed to be soldered. You just plug it in. - Ki Tried to post this yesterday but my attempt was bounced back as spam. Here's my question: After the digital frequency went blank on my TR-7 I pulled the DR-7 board and reseated all the connectors. The single coaxial cable that has to pulled to remove the boardis the center conductor supposed to be soldered in place on the small board it connects to? It did not feel soldered in place when I removed it and the thin blue wire initially. And unfortunately, when I replaced everything the digital display did not come back. Ken - N0VA *** ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] DR-7 board re-install to TR-7
Thanks to all who responded that the coax connection I asked about is a plug-in connection and not soldered. Anyway, after re-seating the pins under the board and the connectors on top of the board the digital display still did not work and I do not have any test equipment. The easiest thing to do was check all 5 of the top of the board connectors again and I found that P3 was apparently still not making good contact with the pins. DeoxIT was applied and the digital display suddenly re-appeared. Low tech miracle. Thanks again to all, Ken - N0VA ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] desolding tool
http://www.mcmelectronics.com/search.aspx?C=K=21-8240T= Cheap and very good at thru hole --- On Thu, 2/11/10, Jim Wagner bjwag...@bresnan.net wrote: From: Jim Wagner bjwag...@bresnan.net Subject: [Drakelist] desolding tool To: drakelist@zerobeat.net Date: Thursday, February 11, 2010, 1:55 PM I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond. -Inline Attachment Follows- ___ 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] desolding tool
Sorry about the first fat finger reply http://www.mcmelectronics.com/search.aspx?C=K=21-8240T= Very effective at thru hole as well as the smaller tube circuits. A spring loaded solder sucker with a gun works well on larger tube items. I must say that I am looking hard at the Hakko 808 based on what I have read on various tech sites. 73, Ron WD8SBB --- On Thu, 2/11/10, Jim Wagner bjwag...@bresnan.net wrote: From: Jim Wagner bjwag...@bresnan.net Subject: [Drakelist] desolding tool To: drakelist@zerobeat.net Date: Thursday, February 11, 2010, 1:55 PM I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond. -Inline Attachment Follows- ___ 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] DR-7 board re-install to TR-7
Ken - Good that it was the connector, and not the IC! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com K Allen wrote: Thanks to all who responded that the coax connection I asked about is a plug-in connection and not soldered. Anyway, after re-seating the pins under the board and the connectors on top of the board the digital display still did not work and I do not have any test equipment. The easiest thing to do was check all 5 of the top of the board connectors again and I found that P3 was apparently still not making good contact with the pins. DeoxIT was applied and the digital display suddenly re-appeared. Low tech miracle. Thanks again to all, Ken - N0VA ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] desolding tool
Hi Jim: I have a very expensive vacuum pump desoldering tool on my bench but I find that the best desolder aid for larger terminals like tube sockets and terminals in the Drakes is braided copper solder wick. I use the wide stuff..I think it is about 3/16 wide, and it is flux coated so cleans and removes solder extremely well. After use on a typical tube pin for instance, I can usually unwrap the lead and remove it with needlenose... without heating it again. Desolder wick is avaialable from all the catalog electronic suppliers..Jameco, MCM, etc. Curt Jim Wagner wrote: I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond. ___ 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, question 2 of 2
Howard - No the trimmers are for the PreMixer plate circuit. The T-4X crystals ARE under the chassis in the left front corner with the panel toward you. They are mounted horizontally, pulling out to the left, and are numbered from front to rear of the chassis. 80 Meter crystal closest to the front panel. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Howard Traxler wrote: Hi all, The 80 meter crystal in my R-4C stopped working so I borrowed the one out of my R-4A. Works fine but now my R-4A needs a crystal. Noticed five holes in the R-4A chassis just in front of the crystals. Might there be trimmers under there that could get that crystal working again? Maybe I could borrow one from my T-4X but I can't find them. Maybe they're under the chassis? Thanks for any ideas. 73, de Howard, WA9RYF ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] RF Signal Generator
On Tue, 2010-02-09 at 12:55 -0500, James Bridgers wrote: I would like to have a rf signal generator for my use. Any suggestions as what to look for? Thanks in advance for your help Since James has not identified what his use is, the wide ranging responses to his question generated answers to the more general question of: What RF signal generators are available? And at what cost?. The very wide range of generator costs identified by other posters to this thread offer few if any inexpensive solutions. Inexpensive probably means build it from scratch or find a kit. As others have mentioned, aside from generating the signal, knowing what frequency it is on and being able to adjust the power level are probably the minimal characteristics of a useful generator. A transistorized wide frequency VFO with band-switchable coils/caps is easily made. This coupled with a frequency counter and a step attenuator makes a useful generation system. A DDS-30, DDS-60 or equivalent is better that a VFO-type oscillator for some applications, but will depend on your needs. Google for Frequency counter kit and step attenuator kit. Scan the unmentionable auction site to see what's available. Having separate pieces of gear is a plus because each may be used in more than a single way. Gear such as a crystal oscillators, RF detectors, RF mixers and the like can be easily added to the mix to give you more testing/experimenting capabilities. Also consider that simple, usable electronic equipment based on the PC sound card are easily fabricated. Do some research, decide build or buy, go for it! Joe, K9HDE ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] desolding tool
I have the Hakko and it works very well for PCBs. There is maintenance, however. You do have to go through a cleaning process. For chassis work, a good spring loaded pump works just fine. Dennis AE6C On Thu, Feb 11, 2010 at 10:55 AM, Jim Wagner bjwag...@bresnan.net wrote: I have been looking for a good desoldering unit that works. I have looked at Hakko and Xytronics. Looking for options of what is a good solution. Thanks to all who respond. ___ 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
