[TenTec] Argonaut 509 from HELL!

[Richard Arland]

Hi Gang:

I have been busy the last couple of days so I haven't had a chnace to relate the latest in the ongoing saga.

Garland Jenkins at the T-T Lab was kind enough to send me a set of coils, one for 10M and th eother one for T1, the mixer/multiplier coil on the Osc sub-assembly, and a set of orange dial pointers (the original ones they sent to me for reubilding the PTO were broken when the arrived). 

I have not had a chance to sub out these two coils yet, that will happen either Monday or Tuesday. In the mean time, I had the opportunity to take the sub-assembly out of the rig (once again) and remove all four active devices (Q1--4) and replace them with 2N2222 in metal cases (this was suggested by Mike Bryce, since he theorized that either the oscillator transistor, Q1, or the multiplier stage, Q-4, might have become leaky over the years and not be able to generate a signal needed for the 10M function). Although Mike thought that I might need to replace only two of the pesky transistors, I decided to do all four. I also replaced the MPSU10 on the Audio board (that I broke due to handling the radio) with a TIP-31, generic NPN in a 220 case (I don't know why I needed to go to such a huge transistor, as I felt that a TO-92 should work OK, however, I followed the suggestions of several of you out there in T-T Land and used a 220 cased NPN). 

During this process, I once again, took a close look at the switch wafers and solder joints. All appeared to be OK, so I left well enuff alone!

So, I am ready, Monday to proceed with the coil replacement and then on to firing the rig up and hoping that it decides to oscillate on 6.333-7.000 MC, and triple to 16-19 MC needed for the injection frequency to get the Argo to play on 10M. 

In the meantime I had the chance to pull the Model 315 receiver out of it's case, hit the controls with DeOxit, clean up the front panel and knobs, and wax them all. Then I did a realignment of the set per instructions in the manual. All went well and the receiver perks right along with an MDS on 10M in excess of -120dBm (I have no external attenuator and the old HP generator won't go accurately below -120). So, for a 35 year old rig, it's hotter than a two dollar pistol! Interestingly enough, the Osc sub-assembly looks almost identical to the one in the Argo from Hell, but I didn't want to chance screwing up the 315 by pulling that assembly and subbing it out in the 509, just to see if it would work. 

Thanks to a charitable friend I have a basket case 505 coming my direction with a 2.1 KC SSB filter (NIB) that I can use for a parts source for the 509 from Hell. It will be nice to get the 8-pole xtal filter into the 509, once I get it perking on 10M. 

All for now. Once again, thanks to all of you who have written with your inputs to my "little project". I can't tell you enough how nice it is to have such talent and help just a few keystrokes away. One other thing: MANY THANKS to Garland Jenkins and the Lab Crew at Seveirville. Their level of concern and their help in this project has been wonderful. They really know what the term "customer service" is all about. 

73 es Happy Holidays.

Rich K7SZ