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Then you see almost no orange with the Eimac tubes when driven with 89 watts? What plate current readings do you get with each set of tubes driven with 50 watts and output power? (I picked a lower

Both import tubes look same color orange This is keyed and 89w drive applied on all bands Idle current approx 100ma total either tube type with hv 2650v Paul K0UYA

I have the crystals listed in this pdf file, both new and used. They were WA8SAJ's

Do both tubes show the same degree of orange? Is this when keyed but with no drive? What is the idle plate current, with the Eimac tubes, then the other tubes? Gary W0DVN

Jim I have two L7, one bonded grids and other stock.? The bonded grids makes more power than stock.? It is the stock one I need to have OK as it is sold waiting to be picked up.? I just want it

Yep, I do agree, I'll dig into the schematic once more ;).. [email protected]> wrote:

That is almost perfect. It has to be in the bridge circuit or the meter itself. Steve Wedge, W1ES/4 Time flies like an arrow. Fruit flies like a banana. Sent from [Proton

Paul, I assume you have the grids directly bonded to the chassis ?? ? That alone will improve stability.? I would leave the suppressors alone. Do you have a hi-pot tester ?? ?One / both tubes

Rob, Bob, and Michael, Thanks for your suggestions.? Looks like the problem noisy tube was V5 (6BA6) Last IF Amp tube. I had a spare on hand so I should be good for now. I had not had the covers off

We are at -1.345 at TP2 detuned and no antenna connected. After swapping V4&V5 I did no adjustment to the circuit. [email protected]> wrote:

I found an eBay photo that shows C1029 as a NP0 temperature coefficient. That's what you will want to use if possible for any added cap. 73 -Jim NU0C "Jim Shorney via groups.io"

In that case C1029 is your target. These radios are over 40 years old. If the crystal was on the edge of tolerance to start with it would not surprise me if it has aged out just enough to make

Where did you see the faint orange glow? If it was in the tube (not on the plate) then the tube has leaked, but surprised it did not just flash over and pop the fuse (and possibly the grid

Please enlighten me Gary.? With the imports installed the tune and load just didn't "feel" right and it was interesting to me that there was a faint orange glow for nominal power output(same in both

Well, aside from marginal vacuum, the RF Parts tubes are good. They just have more gain than the originals, and this makes them more susceptible to instability. There are parasitic choke upgrades

The L7 I recently had instability problems and tune capacitor arc has been REPAIRED.? I managed with time and a jeweler file to clean the burn from the capacitor plate without removing it.? I

I have some general coverage crystals, but no WARC. Rob, NC0B

Also, you can buy new xtals from AF4K: https://yhst-172765969-1.store.turbify.net/drake-4line-crystal--hc49-hol449.html --lyndon

Ken KG8FM writes: Lots of crystals on eBay -- search 'drake crystals'. There's a good selection covering the SW broadcast bands, but WARC band crystals have been pretty scarce of late. --lyndon

I am still on the lookout for an original of the RV-75 manual. The one with the foldout schematics in the back. I am good on QRZ for info. Thanks in advance. Original only not a copy 73? Bob