Radio Shack listed them about a year or so ago under camera items. My local store didn't have one, but I ordered one, paid them, and it arrived in the mail in a few days from their central warehouse. Cost was reasonable, and no charge for postage. I was pleasantly surprised. I have it in my WRL modulator. If you can't find the item, I probably still have the paper work here with the order number.
Another approach which you allude to is to tap off the filament supply with a simple doubler/rectifier/filter circuit. Also, someone told me that he used a small transistor audio transformer in his AF67 to get the low voltage...then as above. I have not tried either, but they are simple enough. Bill w2dgb ----- Original Message ----- From: "Jim Wilhite" <w...@brightok.net> To: "AM Radio Discussion List" <amradio@mailman.qth.net> Sent: Saturday, November 07, 2009 8:31 PM Subject: [AMRadio] Bias Battery >A long time ago I remember someone or several someones talking abut the > modulator tubes bias battery in the AF 67/68. It is a 22.5 volt battery > that I am going to need. I don't recall if the discussion turned into > how to get the needed voltage from something in the radio or the battery > is still available. > > Can someone enlighten me on the subject? If the battery is available, > where? If a modification was performed, how, and where can I get a > copy? Or are both solutions plausible? > > TNX & 73 > > Jim/W5JO > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: AMRadio@mailman.qth.net > To unsubscribe, send an email to amradio-requ...@mailman.qth.net with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > -------------------------------------------------------------------------------- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.425 / Virus Database: 270.14.54/2488 - Release Date: 11/07/09 23:52:00 ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: AMRadio@mailman.qth.net To unsubscribe, send an email to amradio-requ...@mailman.qth.net with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
