Post by outbacktech on Jan 11, 2018 16:29:15 GMT -5
Yes, appears so, no adverse effects, the power supply of the D201 is quite capable of operating this tube and quite well it seems, no real modification to the circuit required apart from lifting the parasitic suppressor off the valve socket, a small hole and a feed from the plate capacitor,
Post by outbacktech on Jan 11, 2018 2:23:49 GMT -5
Yeah, typo, 6 DEE QUE 6, I like Anode caps & the 6L6 ( which is pretty much an Audio Tube) would not work... Yaesu used this Tube back in the days when the D201 was in production in the FT75-B, two of them gave 100w input, the 6DQ6 is better suited for RF applications and a little more rugged than the original, works like a treat in the D201A..
Post by outbacktech on Jan 10, 2018 16:37:29 GMT -5
Ok, many thanks I'll have a look at that this evening, it's really very quiet on SSB RX not even any Psophometric noise which I would expect, just low level hum even with volume flat out, so must be something I'm missing as there aint a lot in the SSB RX circuit after the filter. This is the first D201A that Ive ever worked on so learning...
I had a back and forth with Sandbagger a while back about a fellow that goes by SuperHawk listing old radios at outrageously high prices on Ebay. Well now I have personal knowledge of one of the items Superhawk is currently selling and can say for certain that he is exaggerating the condition of this radio. He recently purchased a Tram D300 that I owned for the past 10 years that I listed on Ebay a few weeks ago. While the radio is in extremely good condition and did come with the original packaging, it was most certainly "used" at best.. However, Superhawk has re-listed the radio (at $1,200 by the way) and specified the condition as "New (other)" with a title of "TRAM D-300 AM/SSB IN BOX / VERY 1ST MADE #87 / X TRAM ENGINNER RIG / CB HISTORY. He goes on to state that the radio was never sold to the public and was a "PROMO radio". Even if he has some irrefutable knowledge that this particular unit, by virtue of the serial number, was never sold by tram through the normal sales channels, it did for sure make its way out to "the public" at least once via Ebay which is how I purchased it ten years ago. His description is at best misleading and at worst a complete fabrication.Su
Superhawk should change his name to Superscam, just like a facebook fellow that I've been observing over the last few month a "Tin Scam Marc" another one to be avoided...
Howdy fella's new the the forum and any advice would help; I'm stuck with this D201A RX issue on SSB it has none.. AM works like a treat -115dBm for 12Db SINAD...SSB is crap.. I have injected a signal straight at the input of T500 (6.255mhz) very quiet with no background noise best RX sensitivity is around -70dBm, appears to be quite a bit of loss through the Xtal filter also measured from pins D16-D19 through the filter around 17dB insertion loss have also injected signal at the C305 junction on board A, still the same low RX. V500,501 &502 all check OK, I'm thinking maybe a SSB AGC issue but can't find any details on how it all works, any advice would be appreciated,, Frank...
Anyone familiar with a modification for the Tram D201 that replaced the normal tube in the output section with a 6146B-8298A tube? Way back when in 1976, my father sent our Tram D201 to a guy to have it modified so that it would transmit on the "manual" tuning selection. At the same time, I remember the guy saying that he bumped up the power, but I didn't know the details. 40+ years later, I fired it up and compared the inside of mine to pictures of units being sold on Ebay. It was only then that I noticed the extra cord connected to the top of the rear most tube in my Tram's chassis (see photo). After examining that tube, I saw that it was a 6146B-8298A. The unit dead keys about 25 watts on AM according to my bird wattmeter.
I have modded mine with a 6DQ6B; One for one swap apart from the anode feed. The plate dissipation on the 6DQ6B is better than the 6DG6, (a whole lot easier to obtain also) a small hole has to be drilled through the chassis to enable a connecting wire from the plate capacitor which needs to be well insulated, the parasitic suppressor is also used again just need to source an anode cap.