[Drakelist] New IRC Channel
I've created a new IRC channel for drake users at freenode.net. Unlike the previous one at irq.net, this channnel can be accessed via a web based client whose operations will be familiar to IRC users. If you haven't used IRC before, it's a great way to stay in touch on a real time basis Hope to see you there. Information on the IRC chat is located at http://zerobeat.net/drakelist/drakechat.html 73, Thom k3hrn ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
Fixed! (Kinda). Replacement of the tantalum cap and retrofitting of the original PTO lamp socket and bulb -- along with the meter light -- cured the problem. HOWEVER, the power meter is now acting up and no amount of re-calibration will help. Forward power readings are fine -- but keying the transmitter in the reflected power postion causes the meter needle to drop below zero. This also happens in the forward power position when the rig's keyed with carrier or mic gain control at minimum. 73, Craig W3CRR ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest, Vol 20, Issue 30
In the past I have not been able to forward anything to theDrake web site. Now that I have changed to a cable network and a new computer I hope this gets thru to the Drake site. Fred M ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest, Vol 20, Issue 30
You are here! Welcome. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com fjmel...@aol.com wrote: In the past I have not been able to forward anything to theDrake web site. Now that I have changed to a cable network and a new computer I hope this gets thru to the Drake site. Fred M ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
On Sat, 20 Feb 2010 11:13:53 -0500, Craig Roberts wrote: HOWEVER, the power meter is now acting up and no amount of re-calibration will help. Forward power readings are fine -- but keying the transmitter in the reflected power postion causes the meter needle to drop below zero. This also happens in the forward power position when the rig's keyed with carrier or mic gain control at minimum. Craig, The zero reference voltage for the meter comes from the 2nd IF/Audio board. This should not change between RX and TX, so you may need to check the zero adjust (R1128) as described in section 3-2 (S-Meter adjustment) of the service manual. This adjustment, as well as several others in the radio, rely on proper setting of the +10V. If the +10V has changed or been adjusted, you will need to re-align the S-Meter/ACG adjustments, and probably the fixed passband adjustments as well. The +10V adjustment is the first adjustment in the service manual, and must be accurately set before any further alignment is preformed. Hope this helps. 73 -Jim -- Ham Radio NU0C Lincoln, Nebraska, U.S.S.A. TR7/RV7/R7A/L7, TR6/RV6, T4XC/R4C/L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time! Give a man a URL, and he will learn for an hour; teach him to Google, and he will learn for a lifetime. HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/ http://radiojim(dot)exofire(dot)net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
On Sat, 20 Feb 2010 20:32:05 +, Nigel Gunn G8IFF/W8IFF wrote: Check for intermittent preset pots on the 2nd IF board. They're all shot on mine. If you replace them, fit multi-turn pots. More likely just in need of a good clean and lube. They have served well for 30+ years, but need a little TLC. Multi-turn is a good idea, but in that location will make adjustment even trickier than it already is. 73 -Jim -- Ham Radio NU0C Lincoln, Nebraska, U.S.S.A. TR7/RV7/R7A/L7, TR6/RV6, T4XC/R4C/L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time! Give a man a URL, and he will learn for an hour; teach him to Google, and he will learn for a lifetime. HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/ http://radiojim(dot)exofire(dot)net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
Hmmm. The 10 volt line is dead on (I equipped the power supply board with trim pots). The S-meter has been re-calibrated correctly with no fuss and the power meter adjustments have been made successfully. Yet, the reflected power still indicates below zero when the transmitter is keyed -- as if the meter was wired in reverse. What about the null meter adjustment on the AL:C board? What does that do? (Yeah, I know -- it nulls the meter). Craig W3CRR ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
OK Craig, I think you have a diva there. Talk to her gently, in low, soothing tones. :) Two possibilities come to mind. The plastic meter case may have acquired a static charge. Have you cleaned the front plastics recently? Vigorous rubbing can excite the electrons too much. This should show as a non-zero reading with the radio powered off. The other possibility is the mechanical zero of the meter movement needs readjusment. Again, does it rest at zero with power off? If so, that's not your problem. This adjustment is accessible from the front of the meter case, which means you have to dismount it from the front panel. Be aware of the potential for static charges while you are doing this, it can throw off the adjustment and you will be frustrated again. The null adjustment on the watmeter board balances the SWR bridge so that you have zero reflected power with a 50 Ohm resistive load. It shouldn't require readjustment, but if you have a good, accurate dummy load, it couldn't hurt. It wouldn't be the source of your problem, however. 73 -Jim On Sat, 20 Feb 2010 20:39:59 -0500, Craig Roberts wrote: Hmmm. The 10 volt line is dead on (I equipped the power supply board with trim pots). The S-meter has been re-calibrated correctly with no fuss and the power meter adjustments have been made successfully. Yet, the reflected power still indicates below zero when the transmitter is keyed -- as if the meter was wired in reverse. What about the null meter adjustment on the AL:C board? What does that do? (Yeah, I know -- it nulls the meter). -- Ham Radio NU0C Lincoln, Nebraska, U.S.S.A. TR7/RV7/R7A/L7, TR6/RV6, T4XC/R4C/L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time! Give a man a URL, and he will learn for an hour; teach him to Google, and he will learn for a lifetime. HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/ http://radiojim(dot)exofire(dot)net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR7 power supply board glitch
Right again, Jim! It was, indeed, a static charge on the plastic meter case. Many thanks and vy 73, my guru. Craig W3CRR ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
