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N_Cook <diverse@tcp.co.uk>: Jun 15 03:40PM +0100 I suspect its use of SMPS type powerfets in the audio side of this , IRFP240/9240 pairs rather than audio grade with whatever is inside of those to reduce chance of oscillation in // use. Anyway replaced those 2 and running with IRF740 in the smps , 60% mains, then put in 2x STW33N60 and amp running ok at 100% mains, fingers crossed. Mods were 20 amp stubs of wire from heatsink to ground pins of the 2 33uF,100V 105deg F caps, I uprated voltage on the replacements as +/-82V unloaded. Added 180pF over the 180pF of C2 to reduce f spec of the amp, bass amp anyway. Aded back to back 4.7V zeners over the back to back 6.2V zener gate protectors of the audio amp, as owner only goes to 60% volume. Added blocks of cured silicone sealant in the easy air paths forcing the air through the heatsink vanes. For the replacement 240 and 9240 ground back the flange bits of the gate pins to take 10mm long ferrite beads, unknown spec <>4K ohm over ends.

Dan <Dan@AIOESPAM.COM>: Jun 14 12:35PM -0700 Looking for a tube only radio or radio kit AM or FM or AM FM More than standard broadcast range is desirable.

Adrian Caspersz <email@here.invalid>: Jun 14 09:23PM +0100 On 14/06/16 20:35, Dan wrote: > Looking for a tube only radio or radio kit > AM or FM or AM FM > More than standard broadcast range is desirable.   Radiation hardened?   -- Adrian C

"pfjw@aol.com" <pfjw@aol.com>: Jun 14 01:37PM -0700 On Tuesday, June 14, 2016 at 3:35:20 PM UTC-4, Dan wrote: > Looking for a tube only radio or radio kit > AM or FM or AM FM > More than standard broadcast range is desirable.   Things useful to know:   a) where are you? b) what is your budget? c) are you in any way handy with tube stuff? d) is portability an issue? Or will this be a mains-driven radio? e) is vintage acceptable? Or do you want something "NEW"?   http://www.xtalman.com/kits.html   http://www.ebay.com/bhp/tube-radio-kit   The links take you to a mixed bag of radio kits - but keep in mind that most of them are toys and 'because they can' devices, not meant for serious (or reliable) listening. If you want that, I suggest you look for a decent existing radio within your budget that meets your needs. I keep several Zenith TransOceanic portable tube radios that receive well up into SW (but have no FM) that might fill the bill. They may be had for as little as US$40 in restorable condition, or as much as $1,500 for certain military models in excellent condition - and the range between.   If you want FM as well, you are in a difficult position - you may have to look at some of the very few tabletop tuner devices made by the likes of Zenith, Heath, and a number of Euro makers (Grundig, Telefunken and Philips come to mind as well as many lesser names) that also include FM. Some of these are tabletop radios with speakers, some even stereo. Others are merely multi-band tuners and require separate amplification and speakers. With the Euro radios, keep in mind that they never used one part where three-or-more would do better, so they are complicated, persnickety, and touchy. When they work well, they are excellent. And when they do not, they are a significant PITA to service, if even possible.   Pick your poison.   Peter Wieck Melrose Park, PA

Tom Biasi <tombiasi@optonline.net>: Jun 14 05:35PM -0400 On 6/14/2016 4:23 PM, Adrian Caspersz wrote: >> AM or FM or AM FM >> More than standard broadcast range is desirable.   > Radiation hardened?   What does it matter. No transmitters will be on.

"pfjw@aol.com" <pfjw@aol.com>: Jun 14 03:49PM -0700 On Tuesday, June 14, 2016 at 5:35:42 PM UTC-4, Tom Biasi wrote: > >> More than standard broadcast range is desirable.   > > Radiation hardened?   > What does it matter. No transmitters will be on.   At least two will be - assuming our survival. And I know of dozens around the world that would survive - again, assuming they are far enough from Ground 0 that the 'wetware' survives.   Not that a great deal of good would come of it. It *IS* the thought that counts.   Peter Wieck Melrose Park, PA

Jon Elson <elson@pico-systems.com>: Jun 14 10:32PM -0500 Dan wrote:   > Looking for a tube only radio or radio kit > AM or FM or AM FM > More than standard broadcast range is desirable.   The R-390 is a pretty nice receiver, all frequencies from near zero to 30 MHz. They are snapped up by hams and collectors, so they get quite expensive. The R-392 has the same range, but is much simpler. It runs off 28 V DC, as both the filament and plate supply.   Jon

Micky <NONONObobbyburns1111@gmail.com>: Jun 15 06:00AM -0400 >Looking for a tube only radio or radio kit >AM or FM or AM FM >More than standard broadcast range is desirable.   If you live near a city, there is probably an antique radio club in it. The one in Baltimore has, iirc, monthly meetings and   RADIOACTIVITY 2016 and the TUBE COLLECTOR's ASSOCIATION Annual Meet 06/23/2016 | RadioActivity 2016 Location: Timonium, MD; Type: ARRL Hamfest Sponsor: Mid-Atlantic Antique Radio Club Website: http://www.maarc.org Swap Meet 8AM, Saturday Learn More   At RadioActivity there are people selling restored radios with wooden cabinets and simple tube radios from the 60's. I went one year and I think I paid $10 for one, hoping it would get a DC station maybe 35 miles away. I can never tell in advance which radios will get it. Brand name doesn't seem to matter.   RadioActivity 2016   HAMFEST/CONVENTION 06/23/2016   Start Date: 06/23/2016 End Date: 06/25/2016 Location: Holiday Inn 9615 Deereco Road Timonium, MD Website: http://www.maarc.org Sponsor: Mid-Atlantic Antique Radio Club Type: ARRL Hamfest Talk-In: None Public Contact: Bruce , KA3EIE 10 Route 99 Woodstock, MD 21163 Phone: 410-461- Email: brucelllllll.md@netzero.net

bitrex <bitrex@de.lete.earthlink.net>: Jun 15 10:09AM -0400 On 06/14/2016 03:35 PM, Dan wrote: > Looking for a tube only radio or radio kit > AM or FM or AM FM > More than standard broadcast range is desirable.   You can build a single-tube regenerative set that, if designed and constructed carefully, will have much better performance over the AM and AM shortwave bands than many commercially available superhets.

Phil Allison <pallison49@gmail.com>: Jun 15 01:36AM -0700 > OH ! I have another reason to believe these are TRFs, > they are two channel, dual mics.   ** So they are cheap and nasty piles of Chinese junk that sell for like $40 ?   No way are they TRF cos that is impossible.       > The side with the lower frequency, some are down like 174 MHz,     ** A 34.825MHz crystal can produce both 208.95 & 174.125 if multiplied by 6 and 5.   To multiply by 6 takes two steps, first by 3 and then by 2.     .... Phil

08springerwrm@gmail.com: Jun 14 06:11PM -0700 On Sunday, June 12, 2016 at 9:49:39 AM UTC-4, Mark Zacharias wrote: > attended to the speaker relay, to replace it or at least (carefully) clean > the contacts.   > Mark Z. Thanks a lot Mark! I bought some Deoxit and glad I'll be able to reach without disassembly. Great info!   Thanks to all for the feedback. Cheap routes first.

rupert handford <rupert.handford@gmail.com>: Jun 14 09:53AM -0700 > > The motor is driven from the analog signal processor that I was asking about, but as the motor does move I guess that it is getting some signals?   > Look at the BA6287F IC. This is hte motor driver IC and is separate from the signal processor. The signal processor will trigger the driver, but the driver itself may be the problem. If the driver has been weakened or damaged because of a bad motor, it may not be able to drive the new one either.   > The way these work is that the CD needs to spin up to a certain speed in a particular period of time, before the focus takes place and an attempt to read the TOC happens. If you are just getting a short shake of the CD, I would start with the motor driver.   Thanks for the reply. Is this routine particular to Denon as I was working on the startup sequence (as follows) from http://www.repairfaq.org/sam/cdfaq.htm#cdstupseq   1. Drawer closes. 2. Interlock (if present) engages. 3. Pickup resets to starting (index). 4. Laser is turned on and focus search routine is started. 5. Disc starts spinning up to 500 rpm and Constant Linear Velocity (CLV) servo is activated. 6. Tracking servo is activated to maintain laser beam centered on track. 7. At this point, data is available for digital processing. 8. Disc directory is read and displayed.   Thus I am assuming that if I get no output to turn on the laser then I will fail focus (I can not find an external focus OK on the driver). Without focus then the disk will not start. This is what is confusing me as I believed that to spin the pre-requirements were that focus is locked and there is a clock present ready to phase lock with the data coming from the disk.   Would love to hear your comments and thoughts on this as I may have the whole thing wrong in my mind.   Regards, Rupert

rupert handford <rupert.handford@gmail.com>: Jun 14 09:54AM -0700 On Monday, 13 June 2016 22:17:01 UTC+1, Gareth Magennis wrote: > And I assume you have removed the soldered safety short that is shipped with > a new laser pickup before trying to use it?   > Gareth.   Yes, I did remove the solder blob when I installed the replacement.

dansabrservices@yahoo.com: Jun 14 10:13AM -0700 I don't know about this particular system, but some attempt to spin the disk PRIOR to the focus. The laser can detect its reflection without needing to be in focus. You may not see the focus attempt before the spinning.   Dan

rupert handford <rupert.handford@gmail.com>: Jun 14 01:25PM -0700 > I don't know about this particular system, but some attempt to spin the disk PRIOR to the focus. The laser can detect its reflection without needing to be in focus. You may not see the focus attempt before the spinning.   > Dan   Thanks Dan, Very interesting - I have ordered both the driver and the ASP from Denon. Will update the post when I get the spares. Best regards, Rupert

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