Looking for B&W 6100 serial number information

[John K5PRO]

I'll check tomorrow on that. The radio had a lot of issues when he got it, such as being far out of tune, and having some broken tuning slugs. It uses a lot of conversion stages for the tube 'synthesizer' so lots to align. As it was supposed to be set up so you didn't need to peak the grid for each new frequency, it had tracking that had to be aligned. A number of the tuned networks are de-Q'ed with resistors to broaden them. I helped him work on it for several weekends last spring. Main symptom was low output on the bands above 40 meters, with nearly nothing on 10. Turns out that the real culprit was a resistor on the 12BY7? driver that was cooked and high value, so it didn't have the gain it should have. Can't believe we missed this time after time.

[w3jn]

Joe, there was an article in an early '60s QST on a xtal synthesizer written by a couple of W3s.  Possibly this was a prototype for the 6100 synth?  In any event I have the actual synth pictured in that article; picked it up at Gaithersburg some years ago.  It still works (or did several years ago) except one xtal appears to be dead.  Covers 5-5.5 MHz.

[W3GMS]

I'll check tomorrow on that. The radio had a lot of issues when he got it, such as being far out of tune, and having some broken tuning slugs. It uses a lot of conversion stages for the tube 'synthesizer' so lots to align. As it was supposed to be set up so you didn't need to peak the grid for each new frequency, it had tracking that had to be aligned. A number of the tuned networks are de-Q'ed with resistors to broaden them. I helped him work on it for several weekends last spring. Main symptom was low output on the bands above 40 meters, with nearly nothing on 10. Turns out that the real culprit was a resistor on the 12BY7? driver that was cooked and high value, so it didn't have the gain it should have. Can't believe we missed this time after time.

John,
Thanks for checking for me.  It sounds like you had quite a job working on the 6100.  It's not a rig for the timid but should work quite well when everything is right. 
Joe, W3GMS

[W3GMS]

Joe, there was an article in an early '60s QST on a xtal synthesizer written by a couple of W3s.  Possibly this was a prototype for the 6100 synth?  In any event I have the actual synth pictured in that article; picked it up at Gaithersburg some years ago.  It still works (or did several years ago) except one xtal appears to be dead.  Covers 5-5.5 MHz.

Hi John,
I will have to look through my early 60 QST's and see what I can find. I have pretty good records of when B & W started various projects, so I will see if I can find exactly when the development of the 6100 started.  I know it was in development for at least 2 or maybe 3 years and as Jack said "they missed the market window" while resolution for various technical issues were implemented.  

Sometime it would be nice to see a picture of that synthesizer you picked up at Gaithersburg.  Talking about prototypes, Jack gave me the prototype of the high stability VFO they were going to use in the T-368.  When they compared it to the Collins PTO, the Collins won out, so that prototype was never used.  

Hope all is well.

73,

Joe, W3GMS    

[John K5PRO]

Th 6100 that Steve, KC5WN, in Santa Fe has is serial number 301. It has some circuit differences from the schematic that is on BAMA, which led to more difficulty in our repairing it. I can put you in touch with him via email if you desire. If they only made 250 or so, did the first one start with s/n 100 maybe?

[W3GMS]

Hi John,

Thanks for the information.  We do have SN 301 on the list and Steve is listed as the owner.   

The list starts with SN 004 so this indicates that they probably started with SN 001.  SN 301 is the highest SN on the list so far.

Regards,
Joe, W3GMS 

[N2ZD]

  Number 280 on the air! Needed two 1000pf 5kv doorknobs.. It was showing a 3:1 SWR everywhere. Replaced the 2 doorknobs located on the plate choke and all is well, one was cracked. Spot on, good audio. Not true AM but good enough. Worked a few stations on 40/80 and rx'ed good reports. Paired up with my R-649 halli.. Richy N2ZD

[KD2AZI]

Resurrecting an old topic here...I'm a new owner of a B&W 6100 Serial #201, and I've been scouring the web for info.

I looked on the spreadsheet posted much earlier, and mine isn't on the list.  I bought it at auction, so I don't know much about its history except that it was very well-cared for, as it's in great cosmetic condition and very clean. 

I replaced a boat-load of out-of-tolerance resistors and a few caps, and have started testing.  A friend volunteered to help me check out a suspcious crystal, and we confirmed the 700 kHz digit crystal is bad; we also determined that these crystals in the 24-25 mHz range are at the fundamental frequency by putting it on an HP network analyzer and visualizing the frequency response.

Just wondering if anyone is still keeping track of the 6100 users, and I'm looking forward in the coming months to getting this thing on the air.

Are there any engineers from B&W still out there?

[W3GMS]

Resurrecting an old topic here...I'm a new owner of a B&W 6100 Serial #201, and I've been scouring the web for info.

I looked on the spreadsheet posted much earlier, and mine isn't on the list.  I bought it at auction, so I don't know much about its history except that it was very well-cared for, as it's in great cosmetic condition and very clean. 

I replaced a boat-load of out-of-tolerance resistors and a few caps, and have started testing.  A friend volunteered to help me check out a suspcious crystal, and we confirmed the 700 kHz digit crystal is bad; we also determined that these crystals in the 24-25 mHz range are at the fundamental frequency by putting it on an HP network analyzer and visualizing the frequency response.

Just wondering if anyone is still keeping track of the 6100 users, and I'm looking forward in the coming months to getting this thing on the air.

Are there any engineers from B&W still out there?

Thanks for the information about your 6100.  I will add you to the 6100 owners list.  If you like, I will send you the latest list for your records.  Jim-W8KGI is the originator of the list but I have been helping him maintain it. 

Please let me know when you get yours on the air.  As far as the crystal is concerned, you should be able to get a replacement from International Crystals. 

73,
Joe-W3GMS