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Saturday: The Inductance to ground running parallel to the RF input from the 50:450 unun is what was missing. I do not understand why 750 ohms swamping resistance is the optimum value given the 50:450 ohm unun, but 750 is spot on. I used a 10T Pot in place of 750 ohm fixed and 750 shows a...

Stripped RF deck down to sockets. Rebuild looking better than my prior mess which worked great on a DL, lol. Antennas not so much. The 3 PSU's (plate, grid, screen) are in order so back to revising RF Input with an attempt to copy Pride's diagram for 10-11-20-40. Received a better Inductance...

Thank you Nomad, wonderfully specific. Diagram shows 10 & 39pF shunt caps for 20 & 40M. Given that 2 tubes is twice 1, is halving the values (to 5 & 20pF) overkill? Someday I'd like to be able to recognize these concepts by sight instead of only copying them. Thank you again.

Removed everything from inside Tube deck, starting fresh. Added terminal strip and ceramic post as foundation for mounting components. Will duplicate Pride input circuit best I can. Have picture of pride Input board to aid in part selection. Have good selection of red & yellow toroid cores to...

Never saw a POW amp but you say it's tube and all AC, even the relays? If true, are you willing to change out the relays to make them DC, too? Only AC relays in amps I saw were old amps like late 1950, early 1960 models and they had 115vac relays. So be it, not impossible. Making DC for a...

CB Tricks was the place for a long time. RF Parts sells the 1:9 toroid from old Pride stock so I ordered one plus an assortment of fixed, factory-made inductors. I can also wind my own as I try to copy the Pride input but for 2 tubes. As for the Pride RF Input, there’s a lot to respect given...

Nomad's DX-300 manual has RF input coil inductance values for each Band. Thank you that's a big help.

It's been over a year since I looked at Pride diagram and it feels good seeing it again with more experienced eyes. The cap & inductor pairs to ground switched in parallel to a direct grid driving connection post resistive ground is curious. I expected an all or nothing switch-action but the...

Thank you for the feed back. I got some 10M gains by placing a roughly 1uH inductor across the grid connecters on other side of socket last night. 20 still dead and 40 always good. The added inductor connected the 2 grids together and was Parallel to the RF drive connection on other side of...

Edit 3: In for a penny in for a pound. Ordered a better Inductance meter. 1 uH is so small. Removed Edit 2 coil and reattached lead to grid from balanced output. Installed inductor across grid terminals on other side of tubes. I need to measure with more accuracy than I can now. Meter...

The grid inductance you describe is series inductance right? It was inevitable that after amp basics in place, I would need to re-visit 'inductance in the grid circuit'. I got lucky here and there but it's time to address this. Thank you for quantifying it around 1uH Nomad. Thats a good...

FT-891 back from Yaesu, 11 days R/T:). They've seen this issue before. Radio seems to run cooler. I’m flustered at how long it took me to realize the ‘low noise level’ was from no Receive. I need a better sense of humor. Shortcomings aside, SMT diode failures like this are what kept failing...

Got Repair Completed email from Yaesu. From the Cypress CA location: FT-891 repaired and shipped back FedEx. Less than 10 days total. I got lucky? 3 year warranty, I'm impressed with that. Low hanging fruit to say more impressed if it never failed as I drive homebrew amps and a lot of...

Yesterday I sent my 891 to Yaesu. I have 6 mos left on Warranty. The issue is that I lost Receive sensitivity. I'm less than 4 miles from the 4U1UN Beacon atop the United Nations and I can barely hear the 100w intro and my noise level is zero-ish at all times on all freqs. I've been so...

The setting mentioned by ADE587 (07-11) cured that issue for me. LOL someday re-do Mars mod & lose all my Memories :confused:. Only concern I have now about the 891 is that it runs so hot on Receive. I keep PSU at 12v but no change. I'm about to measure Receive only current. Supposed to be...

COR works Nomad! Have not tried SSB yet because I still need to locate the switch somewhere. Reluctant to drill more holes, running out of metal lol. Only tested AM at 5w (lowest PO on FT-891) but worked right away. Thank you.

Thank you. I should have known how to do that given what I'm doing and it's embarrassing I did not. My transformers are all fed separately from the SS module which is powered from the Mains fuse at 16A. I'll start with a 6A fuse for the Ext transformer and if it holds that should do it.

'dead short yeah' yeah I saw that lol. All ok as I used reduced/isolated test connects at first. When I finally got it working on full power I still used Temporary connections (wires strewn across the floor) --it worked really good though. Yesterday I began to making wiring permanent where...

Had to step back. The external plate xfrmr project was causing me anxiety. Scrapped the notion of trying to use a 2nd AC outlet. Got tired of replacing fuses and it's not a good idea. Connecting the Ext primary to the Soft Start module is best. It eliminates the power-on sequence issue. Got...

Parallel Xfrmr successful! Easily >1kw :giggle: into DL. That straining noise/hum from being underpowered is completely gone. Tomorrow I'll try the 20A Air Conditioner outlet near operating location after I seal it up again. I fused the external Xfrmr ("X") Hot lead to primary. Began...