The AM Forum
March 28, 2024, 10:42:46 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: 1 [2]   Go Down
  Print  
Author Topic: Viking Valiant Turbo version ( the restoration begins!)  (Read 31992 times)
0 Members and 1 Guest are viewing this topic.
Steve - WB3HUZ
Guest
« Reply #25 on: February 22, 2005, 08:18:54 PM »

100 watts to drive the grids of the 6146s? I hope not.

The  10 watt tranny should be fine. I don't know about the impedance ratio though. JS clip lead it in and see if it works.
Logged
John Holotko
Member

Offline Offline

Posts: 2132



« Reply #26 on: February 22, 2005, 11:48:23 PM »

Quote from: w3jn
Wow!  Someone went loco installing random meters on that poor xmitter!

There's no restoring it unless you get a new front panel.... they show up from time to time on eBay and hamfests.  Other than that it doesn't look too bad.  I guess I'd just get it working, do the standard audio modifications, and enjoy it as is until you find a new front panel.

73 John


I have a spare panel for a Viking Valiant 2. Unfortunately the rig in question looks like a straight up Viking Valiant. Dunno if those panels are interchangeable.
Logged

N2IZE<br /><br />Because infinity comes in different sizes.
xe1yzy
Member

Offline Offline

Posts: 348


« Reply #27 on: February 23, 2005, 11:52:01 AM »

Quote from: Steve - WB3HUZ
100 watts to drive the grids of the 6146s? I hope not.

The  10 watt tranny should be fine. I don't know about the impedance ratio though. JS clip lead it in and see if it works.


Ok Steve thanks a lot, I have some transformers for " cut and try", smokes its part of the joy isn't?
Logged

TVI WHAT TVI?
xe1yzy
Member

Offline Offline

Posts: 348


« Reply #28 on: February 23, 2005, 11:56:51 AM »

Quote from: John Holotko
Quote from: w3jn
Wow!  Someone went loco installing random meters on that poor xmitter!

There's no restoring it unless you get a new front panel.... they show up from time to time on eBay and hamfests.  Other than that it doesn't look too bad.  I guess I'd just get it working, do the standard audio modifications, and enjoy it as is until you find a new front panel.

73 John


I have a spare panel for a Viking Valiant 2. Unfortunately the rig in question looks like a straight up Viking Valiant. Dunno if those panels are interchangeable.


Hi John...

many thanks,No it is not a Viking II, is a viking valiant,, and Im already have a panel replace , I update the pictures you can see the new panel there.
http://www.angelfire.com/electronic2/xe1yzy/Viking/index.album?i=2
73'S Pedro
Logged

TVI WHAT TVI?
John Holotko
Member

Offline Offline

Posts: 2132



« Reply #29 on: February 23, 2005, 12:55:50 PM »

Quote from: xe1yzy
Quote from: John Holotko
Quote from: w3jn
Wow!  Someone went loco installing random meters on that poor xmitter!

There's no restoring it unless you get a new front panel.... they show up from time to time on eBay and hamfests.  Other than that it doesn't look too bad.  I guess I'd just get it working, do the standard audio modifications, and enjoy it as is until you find a new front panel.

73 John


I have a spare panel for a Viking Valiant 2. Unfortunately the rig in question looks like a straight up Viking Valiant. Dunno if those panels are interchangeable.


Hi John...

many thanks,No it is not a Viking II, is a viking valiant,, and Im already have a panel replace , I update the pictures you can see the new panel there.
http://www.angelfire.com/electronic2/xe1yzy/Viking/index.album?i=2
73'S Pedro


Okay, I am glad to see you got the right panel for the transmitter. I saw the pictures, it looks nice.  The Vikings and Valiants make for nice restoration projects.

Regarding the spare panel that I have available should anyone need it I should have been a bit clearer. It's a Valiant 2 panel not a Viking 2 panel. Apparently Johnson made 2 versions of the Valiant over the years. The Valiant and the Valiant 2.  The primary difference between the 2 rigs was the design of the panel. The Valiant 2 front panel was designed to have a more "modern" look for it's time. It's grey and silver with metalic silver trim and brushed aluminum knobs. From what I have been told Valiant 2's  are relatively rare.

Anyway, glad to hear you got the parts you need. Good Luck with the Valiant restoration project.

73's

N2IZE
Logged

N2IZE<br /><br />Because infinity comes in different sizes.
Steve - WB3HUZ
Guest
« Reply #30 on: February 23, 2005, 08:46:02 PM »

I hear most of them, along with Viking IIs wound up on the CB band.
Logged
W8ER
Guest
« Reply #31 on: February 23, 2005, 11:48:59 PM »

Pedro,

I want to give you a slightly different approach to look at. Please click on this link and notice the modification that Gary W3AM made to his Viking Ranger. It is taken from the Ranger modifications originally documented by Tim WA1HLR.

http://www.w3am.com/ranger.html

In this change, the driver transformer is eliminated entirely. I have found that most of the limitations in both the Ranger and the Valiant center around this transformer. The phase inverter circuit, suggested in the diagram shown on this page, has worked very well for me. It eliminates the fidelity restrictions imposed by the orginal driver transformer.

It is so simple and requires but a very few inexpensive parts. In both my Ranger and in my Valiant I use this same circuit, one half of the 12AU7 as a phase inverter and the first half as a voltage amplifier, preceeding the phase inverter. I feed line level audio into a UTC A-11 transformer, which matches the balanced line level audio from my audio equipment into the grid of the first half of the 12AU7. I also mix audio from the microphone preamp in at this point. The old clipping coltrol is line input gain and the old audio pot is the microphone gain. You can choose one or both audio sources this way.

If you choose to try this circuit there is one caveat! When you wire in the voltage to the plate of the phase inverter, you must find another source of HV for that tube. In the Valiant, the HV is switched off and on (transmit to receive) and in doing so the coupling caps to the grids have to charge, causing a very heavy mod current spike. I believe that I tied it to the low B+ (380 volts) and that worked fine.

The 6146's are biased to run in AB1 and provide plently of audio for the finals. For a while I removed one of the 6146's from the finals, making it a pair modulating a pair. I was concerned mostly with the heat and the extra loads placed on the transformers by running it where Johnson wanted it run. By removing that tube and solid stating the power supplies, a lot of heat was eliminated.

Later I put the extra 6146 final back in and it's fine that way too but I still only loaded it to about 230 ma. This gave me 105 watts of nicely modulated RF out. I loaded it heavier to test it and still could modulate it well but not with the reserves that gave me good asymetrical positive peaks at the lower power settings. I doubt that anyone that listened to the Valiant could tell that it wasn't running the full 145 watts .. the difference was not important.

The Valiant mod iron suffers from the same characteristics as the Ranger's in that the waveform starts to show funny lumps and bumps below 150 hz. The mod transformer is not the best but it does sound real good and works fine. I generally roll off audio under 200 hz anyway.

This mod has worked very well for me. I used this phase inverter circuit on an Apache also and it also sounded very nice. In this case it was a pair of EL34's instead of 6146's (slight different bias settings) being the only difference. In fact, I use EL34's in my Ranger too but the same phase inverter circuit.

Best wishes on your restoration, no matter which way you choose to do it, I am sure it will sound great!

--Larry W8ER
Logged
John Holotko
Member

Offline Offline

Posts: 2132



« Reply #32 on: February 24, 2005, 12:15:24 AM »

Quote from: Steve - WB3HUZ
I hear most of them, along with Viking IIs wound up on the CB band.


Sadly that is true. A lot of them wound up in the hands of CB'ers who didn't know what the heck they were doing with them. Many years ago someone gave me a basket case Viking 2 that was in very sad shape.  I wound up using it for parts.
Logged

N2IZE<br /><br />Because infinity comes in different sizes.
John Holotko
Member

Offline Offline

Posts: 2132



« Reply #33 on: February 24, 2005, 12:16:59 AM »

Quote from: W8ER
Pedro,

I want to give you a slightly different approach to look at. Please click on this link and notice the modification that Gary W3AM made to his Viking Ranger. It is taken from the Ranger modifications originally documented by Tim WA1HLR.

http://www.w3am.com/ranger.html

I

--Larry W8ER


Hey, thanks for running this by here on the board. I have a  Valiant that I am working on right now and I might wind up putting some of those idfeas to work.
Logged

N2IZE<br /><br />Because infinity comes in different sizes.
Steve - WB3HUZ
Guest
« Reply #34 on: February 24, 2005, 09:23:20 AM »

Quote from: W8ER
I have found that most of the limitations in both the Ranger and the Valiant center around this transformer. The phase inverter circuit, suggested in the diagram shown on this page, has worked very well for me. It eliminates the fidelity restrictions imposed by the orginal driver transformer.
--Larry W8ER


I'd say this is true of just about every 50's vintage plate modulated AM rig. Nearly all of them used a severely undersized driver transformer in concert with a single-ended Class A driver tube. This was a good recipe for saturation of the driver transformer and lots of distortion. There was some logic in using the tranny on the rigs with Class AB2 modulators. But in rigs like the Ranger where the modulators could easily be run AB1, the transformer made no sense.

Getting rid of the single-ended driver system is almost universally a good thing. Getting rid of driver iron is too. For detailed instructions on how to install a nice phase-splitter driver for the Valiant, see the link below.

http://www.amwindow.org/tech/htm/valiant/valiantmods.htm
Logged
xe1yzy
Member

Offline Offline

Posts: 348


« Reply #35 on: February 24, 2005, 11:24:12 AM »

Quote from: W8ER
Pedro,

I want to give you a slightly different approach to look at. Please click on this link and notice the modification that Gary W3AM made to his Viking Ranger. It is taken from the Ranger modifications originally documented by Tim WA1HLR.

http://www.w3am.com/ranger.html

--Larry W8ER


Hi Larry

Thanks a lot for your comments and the information, Gary's circuit looks great, I guess is exactly what im looking for my Viking's,actually I have 2 Valiants and one Viking II, so this information are very valuable. one think I likes is the fact that this circuit dosen't needs any sophisticated part. well, for the moment Im working in the P.S. and the VFO, I want a steady voltage and steady frecuency control, by the way Tim WA1HLR, have some very good ideas about VFO improving also.

Many Thanks Larry,  Nice Avatar!
Logged

TVI WHAT TVI?
xe1yzy
Member

Offline Offline

Posts: 348


« Reply #36 on: February 24, 2005, 11:41:16 AM »

Quote from: Steve - WB3HUZ
I hear most of them, along with Viking IIs wound up on the CB band.


Steve...

Im also saw the vikings used as a CB, and as a CB amplifiers, of course there is also ilegal in Mexico, but even today, among the CB operators , you can find  a FT-1000 as a CB station!
Logged

TVI WHAT TVI?
Pages: 1 [2]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.039 seconds with 19 queries.