Just wanted to give an update - I have the tx bandpass transformer working now.  Someone in the past had messed with this with the golden screwdriver, as the top core that was not stuck was wound almost the whole way out of the can.  The bottom one appeared to have been driven down to the bottom and jammed there and I believe split.  I removed and opened the can, was able to break apart the bottom slug and get all the pieces out with a dental pick and a carbide bur in a dremel.  I then sanded down a same sized donor core so that it would not be tight fitting and ran it up and down to make sure it would go smoothly.  Then reassembled the can, put it back in circuit with no leftover parts and with a little adjustment was able to finally get TX signal through the driver stage (the bandpass coil was so far out of alignment originally nothing was getting through to the driver).  Just a few more gremlins to go.

Not sure if I should start a new thread or continue this one - another question on restoration of this same radio.

I am making progress - power supply working, and receiver is coming to life on all bands.

Trying to go through the alignment process from the manual and found that a slug in one of the bandpass filter cans seems to be "frozen".  It is a dual slug can, and the top slug I was able to move, so it is not against the bottom slug top but the bottom slug will not turn in ether direction.

Any tricks or suggestions?  Anything that can be applied to loosen up the stuck slug?  I guess worst case is dismantle the can and drill out the slug and put in another similar sized slug from a donor can?

I hope to get this thing working and am happy with the results so far.  still need to work out an agc issue and an intermittent speaker wiring problem and then move to transmitter once everything else is fine.

Thanks,
Bob
 

Sorry if this sounds like a silly thing to check, but several old radios I have messed with before had normally closed switch contacts used on the key jack so that if no key was plugged in the key jack was shorted so that when you flipped to cw position it could be used as a "tune" setting.

Try plugging in a key and see if it stops.

Chris,
The post about looking for EHC knobs helped.  Ebay or several vendors sell EHC knobs that are very close to the originals.  Of course the hard to find one is the main tuning knob which on the original was a spinner style that may have been a custom one for the radio.  Closest I could find for that was a EHC knob made for various Henry radios and military equipment, but it had a black plastic center instead of the aluminum of the NCX-5, so I just used a solid aluminum knob that I found cheap to start with, and will decide later how far to go with the restoration depending on how the electrical side of it goes...

Brad,
I think you mixed me up with someone else.  I purchased this one from eBay in california.  It was received in the condition of the photos, so no problems with that.  The suggestion about EHC knobs really helps.  Am waiting for a proper power supply for it to start getting into the function of it, and was starting finding the right knobs to make it look more presentable.  I think I found the right ones and ordered some, will see what they look like when they come in.  I used to use an old NCX-3 many years ago and thought I would pick up an NCX-5 and see if I could get it running again.

Thanks for the suggestions!  I may be asking for more suggestions once I get it powered up depending on what I run into.

Bob

Hello,
I am restoring an old NCX-5 mk ii and saw there have been some talk of those on here.  Does anyone know where I could find some replacement knobs for one?  The bandswitch knob is cracked (it is one of the pointer style).  I may be able to repair it.  The other knob it needs is probably made of "unobtanium" - the main tuning knob is the way most of these seem to get, the spinner portion is broken off and missing along with the spun aluminum center.  Could probably make a new aluminum center, but the cracked off portion of the knob would be hard to make look correct.  I think another problem with these knobs is I believe they were attached with lead melted into holes in them making them almost permanently attached to the shaft they are on, so might need replaced as an assembly if they can be found.

Might have to just find another style knob and see what can be done with it.

Thanks,
Bob

Thanks for the replies.  I did make another attempt at neutralization and finally got it working a little better on 10 meters.  I probably need to go back through the whole thing to make sure the alignment is all good now that it seems about finished.  Nice to resurrect an old rig and get it usable.

Just curious if anyone had suggestions for an old Galaxy GT-550.  I picked it up as a parts rig really cheap on ebay last year and it seemed like enough of it was together that I resurrected it and actually have it running fairly well.  Receiver works, and transmit works on all bands but 10m.  I am wondering if it is just that all the tubes are just really old now and won't work well at that frequency or if anyone had suggestions - there is drive, but on 10m it just seems unstable - instead of a "dip" for the plate, it will "peak" so I assume it is getting parasitics.  I rebuilt the parasitic suppressors, tried adjusting the neutralizing capacitor, tried a different set of finals, but the behavior stays the same.  I don't really need to use it on 10m, but it just bothers me that this one piece does not work.  I have the remote vfo, a homebrew calibrator, the vox, and correct power supply, so it is a nice complete station with the exception of 10m TX.  Funny that I paid under $50 for the main "parts" rig and just the other week someone paid over $400 for a bare 550 unit minus power supply or accessories untested because it was advertised as "mint" on ebay.

thanks for any suggestions,
Robert

Thanks for all the input - I finally placed an order for one of the LP100A units.  It costs as much as a 30 year old Bird, but I decided that I would go ahead and buy it, you can't take it with you and the way this country is going its not like the money is going to be worth anything if you leave it in the bank

Thanks for all the comments.  I will take a look at the different options suggested.  The "wattmeter" I have is a very beat up and well used heathkit from a ham fest that I have no trust in, I want something that at least is starting at a somewhat known calibration.  Someone asked what the amp was, it is an old XR-3000D.  I am just running off 120V as my only 220 outlets are in my garage and it is more or less a play project.  I added a soft start relay, fixed a too high filament voltage, and the main thing I had to do was change around the bias circuit.  The design had a 12v zener for the transmit bias, and every document seemed to indicate that these tubes (at around 2700v for plate) needed about half that for bias.  It was biased to cutoff even when in transmit, so I changed out the bias circuit and used a string of diodes to get bias to around 120ma (what manual said it should be), and I drove it to over 1500w input with no signs of overheating or anything.  This made me realize my garbage wattmeter was not really working as at higher frequencies it was showing output so low that the tubes would have been showing signs of heat if that much power was being lost in the amp, but the amp was running along with no heating at all, and loading normally, so I am fairly certain that the hamfest special battered meter is just not working right.  It has given me readings on other transmitters that I did not think made sense as well, so I am going to invest in something better.  I just can't see spending the price they ask for a 30 year old Bird and a couple slugs.  At that price I think I should be getting a more usable meter, not another 30 year old used meter that I still would be suspicious of without another method to verify it.

Thanks again for all the input.

Not sure if this is the correct forum, but I recently got fixed up an old linear that uses a pair of 3-500Z tubes.  I do not really have an actual watt meter, all I have is an heathkit SWR meter which has a wattmeter function but I would be surprised if it is anywhere close to actual readings, and I do not believe it is linear with frequency (reads much higher at low frequencies than high with any transmitter).

What do you recommend as a decent wattmeter that at least would give semi accurate readings (I am not talking lab quality here).  It just seems silly to put more money into an old used Bird 43 and a couple elements than the entire amp cost.  I see an "LP100A" advertised on this site for probably less than a bird and a few elements, but $435 still seems high for a wattmeter.  I guess I am just being cheap

Any recommendations?

I believe the proper microphone connector for what you describe is a switchcraft 2501F.  Do an ebay search for 2501F and you should be able to see if that looks like the connector you need.

I am playing with getting this old set running.  I have powered up the receiver on batteries and it works fine, but I am looking at powering the transmitter.  It looks like it needs 425 - 500v for plate and 6v for filaments.  My really dumb question is this - would it be ok to run the filaments off of a standard 6.3v AC or do these have to be DC?  The tubes appear to be directly heated cathodes, so I am guessing this would add hum into the TX?  I was hoping to have to avoid building some sort of high current regulator to get a stable voltage for the filaments, I cannot find the current draw documented.  I have some old transformers that I can probably slap something together with, but it is just so tempting having a 6.3 vac winding sitting there just begging me to avoid trying to rectify then regulate it to keep it from feeding too much to the filaments.  I guess I could string a bunch of forward biased diodes to ground as a crude regulator as long as I chose a correct series resistor with enough dissipation.  I may end up just grabbing some high wattage slider adjustable resistors and kludge something together.

Thanks,
Bob
ka3iwu

Thanks for the link and the advice.  I will try to feed it some RF this weekend if I can get the time away from my job.

I have not tried applying drive to it yet, I was trying to move slowly with it and not proceed until everything looked good.  It just seemed that since the manual called for 100ma of idle current and I was seeing 26 that something was wrong that I should fix before trying to apply drive.  Maybe I should try it anyway and see what happens.