Johnson Ranger: Can't Find The Chirp!

[W1TTL]

Hi everyone,

I have been chasing down the chirp that sounds like bloop-bloop on my Johnson Ranger for a couple of months now to no avail.  (If you've heard lots of bloops on 40m, it's me!  It's so bad, RBN doesn't pick me up!) I've recapped all the electrolytics and changed out R3 -- all the regular stuff.  When I switch to a crystal at 7.100, my CW tone is nice and solid.  When I switch to the VFO, on any frequency on 40m or 20m, my CW tone bloops. 

Since it seems to be related to the VFO, I replaced the 500pf mica capacitors, the 5000pf ceramic capacitors, as well as C15 with a 43pf capacitor in the VFO as well as any resistors that seemed out of spec.  The OA2 is putting out around 150VDC.  I have the add-on keyer platform (I have an early Ranger), and I replaced the capacitors in there as well as any resistors that were out of spec.  I also did the chirp mod suggested here: https://www.w8ji.com/johnson_vfo_chirp_jump.htm

Nothing I've done seems to have helped the chirp.  Also, when I key down, the pitch slightly changes, as if the VFO can't stay steady.  Can anyone point me in the right direction?  I'm pulling out my hair here.  I haven't changed either of the tubes in the VFO (unfortunately, I don't have a tube tester).

Here's the funny thing: the tone sounds perfect on 80m and 160m but not on 40m or 20m.  No bloops, no drift on 80m and 160m with CW.  I've also had good AM phone reports on 80m.  I feel like this a hint to what's going on.  Before I continue, I thought I'd seek out some wisdom.

Thank you for any guidance!

73,
Tony W1TTL

[WBear2GCR]

Replace the tube in the VFO, if you haven't.

How is the rig being keyed for CW?
Is it grid block or are you trying to key the HV for each dit or dah?

                 _-_-

[w4bfs]

Just recently working on ranger ... there are 4 old style silver mica caps in vfo cmptmt 2 500 pf and 2 1000pf ... 300v caps are fb ... these need to be changed regardless of chirp or not because if the mean old dendrite gets you you may not have a vfo at all.

recommended to remove 0A2 and 18k resistor from cmptmt and mount outside...also change wiring to remove 300V from vfo plate and power the 6au6 from reg 150V .... if your low voltage is indeed 325V and not much more (as in improperly solid-stating the power supply) then add a 22k 1/2W resistor to feed the screen and add a 20K 2W in parallel with the 18k 2W resistor feeding the 0A2..  noted 100Vpp out on 40M after modification.  I added a 325 V regulator to keep these voltages proper.

I am taking this ranger I have to series modulation with a full power out for linear amp tuning ... hope to be Ota soon

[WU2D]

Well yeah it could be the tube - change the 6AU6 out and if you have not yet, and clean the socket and the rotary contacts. Oh and loosen and spray and retighten all of the fasteners around the tube socket and VFO compartment.

Good luck! Mike WU2D

[W1TTL]

All,

Thank you all for your suggestions.  I fixed it.  The culprit ended up being C11, a 62pf NP0 ceramic capacitor in the 40m and above circuit inside the VFO.  For those of you who know where this is in the VFO, you can imagine how much fun it was to replace.  Now it doesn't bloop any more on 40m or 20m.  No more chirp, either.  (And yes, you will get a chirp on 40m if any part of the VFO cage is open when you're testing this on the bench!).

Thanks and 73,
Tony W1TTL

[w4bfs]

nice going Tony .... that's not an easy troubleshoot or fix .... down here in the HUMID south gives us more trouble with the old silver micas

[W1TTL]

W4BFS,

Thanks!  And I had changed out all the mica caps in the VFO before I went after the ceramic capacitors since those were easy to get to.  At least now most of the capacitors are changed out in the VFO!  I have the rig on the air right now.  I am going to let it warm up for 30 minutes to see if the VFO stops drifting ever so slightly.  At least RBN is picking me up on 40!  It wasn't doing that before!!!!

73,
Tony W1TTL