Re: [Drakelist] Posting a request
Ron - I've not seen an answer to your question. I don't KNOW the answer, but the crystal in that oscillator is operating in the parallel resonant mode, (not typical for solid state circuits,) and about 95% of parallel resonant crystals are specified for a 32 pF load. I have seen a few spec'd for 20 pF load, but not sure why. Anyway, I suspect ICM will be able to tell you what is correct, or may be able to calculate from the schematic. At worst you could specify 32 pF and see what happens! The effect of incorrect load is a frequency deviation, and L1005 gives 'some' range of adjustment. Let us know what you find! 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 Ron Ries wrote: Hi All, i have posted this request several places on the internet and tried to listen in to the Drake Tech Net but couldn't connect. I am restoring a Drake TR-7A and the 13.695 MHz VCXO crystal has drifted way off frequency. I am trying to have a new made at ICM. I also have ordered on from John Kriner but need the following information: What is the load capacitance for this crystal in the VCXO application? Thanks! Ron KK7KZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Posting a request
Ron - OK, so much for my 'expertise'! :-) Looks like this may be one of the 5%. Someone emailed me direct saying that they had sent the old crystal in to ICM and they were able to provide a correct replacement. I'm not sure how that works, perhaps they 'knew' what it should be, -OR- perhaps if they knew what frequency the BAD crystal was on, they were able to check for the correct load at that frequency?! You might consider sending your old one in along with the frequency you're getting with L1005 at mid range. 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 Ron Ries wrote: Thanks for the response, Garey. I did specify 32 pf and have received/installed that crystal only to find that it was, according to Royden Freeland at ICM, too stiff. I replaced the ferrite slug with a brass slug and was able to pull it in and calibrate the radio but it is operating at the extreme end of the operating range of the adjustment pots. An engineer from the UK has looked at the problem and he thinks, at the moment, that 22-23 pf will probably do the job. I'll post the results for others who encounter this problem. Ron On Oct 3, 2011, at 2:07 PM, Garey Barrell wrote: Ron - I've not seen an answer to your question. I don't KNOW the answer, but the crystal in that oscillator is operating in the parallel resonant mode, (not typical for solid state circuits,) and about 95% of parallel resonant crystals are specified for a 32 pF load. I have seen a few spec'd for 20 pF load, but not sure why. Anyway, I suspect ICM will be able to tell you what is correct, or may be able to calculate from the schematic. At worst you could specify 32 pF and see what happens! The effect of incorrect load is a frequency deviation, and L1005 gives 'some' range of adjustment. Let us know what you find! 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 Ron Ries wrote: Hi All, i have posted this request several places on the internet and tried to listen in to the Drake Tech Net but couldn't connect. I am restoring a Drake TR-7A and the 13.695 MHz VCXO crystal has drifted way off frequency. I am trying to have a new made at ICM. I also have ordered on from John Kriner but need the following information: What is the load capacitance for this crystal in the VCXO application? Thanks! Ron KK7KZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Posting a request
Hi All, i have posted this request several places on the internet and tried to listen in to the Drake Tech Net but couldn't connect. I am restoring a Drake TR-7A and the 13.695 MHz VCXO crystal has drifted way off frequency. I am trying to have a new made at ICM. I also have ordered on from John Kriner but need the following information: What is the load capacitance for this crystal in the VCXO application? Thanks! Ron KK7KZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Posting a request
Ron, It doesn't matter. When you call International Crystal, you just tell them what crystal from what radio and they have all the specs. 73, Evan, K9SQG -Original Message- From: Ron Ries rr...@xmission.com To: drakelist drakelist@zerobeat.net Sent: Sun, Oct 2, 2011 12:35 pm Subject: [Drakelist] Posting a request Hi All, i have posted this request several places on the internet and tried to listen in to the Drake Tech Net but couldn't connect. I am restoring a Drake TR-7A and the 13.695 MHz VCXO crystal has drifted way off frequency. I am trying to have a new made at ICM. I also have ordered on from John Kriner but need the following information: What is the load capacitance for this crystal in the VCXO application? Thanks! Ron KK7KZ ___ 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] posting
hi, i cannot remember how to do a posting on drakelist! can you help me? thanksROGER DALE WILLIAMS ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
Uh, you just did!! Just type drakelist@zerobeat.net and go for it!! 73, Don, WB5HAK___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
Oops, I left out some I intended to do. You just simply address an email to drakelist@zerobeat.net then put a subject to it, and then just type in the body what you want to say, Roger. It's really that simple. 73, Don, WB5HAK___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
Roger,Whatever you just did worked.Bill, WB9CAC--- On Fri, 1/22/10, roger williams radior...@yahoo.com wrote:From: roger williams radior...@yahoo.comSubject: [Drakelist] postingTo: drakelist@zerobeat.netDate: Friday, January 22, 2010, 1:08 PM hi, i cannot remember how to do a posting on drakelist! can you help me? thanksROGER DALE WILLIAMS -Inline Attachment Follows-___Drakelist mailing listDrakelist@zerobeat.nethttp://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
This is a test to see if this post actually goes chronologically under the thread Roger Williams started on posting. The problem is that we started a successful thread down below, and then wanted to post with-in this thread, after others had posted. Instead, we ended up with an orphaned post. How do you move an orphaned post back into the thread where it belongs? Thanks, Peter Hoon___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
Oh, I didn't know you had bounces earlier. I'm not smart enough to know how to help, but Thom will likely come on and tell you. Any time I've had bounce problems, it was my ISP. Thankfully I have a good one now that is a ham and understands these things!! 73, Don, WB5HAK ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] posting
Copy and paste, and then send again with the same SUBJECT line. When you say thread what do you mean? Are you reading these on some web site or something? From: Peter Hoon pho...@gmail.com How do you move an orphaned post back into the thread where it belongs? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
