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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 12:08 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
I want to thank everyone for putting up with my nerves ending Viking Issue.
The update is NO more fuse blowing, the bad news my meter isn’t working it’s all the way over to the left. Any way to check the meter?


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 12:28 am 
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Joined: Jan Tue 10, 2012 8:39 am
Posts: 1965
It's probably not the meter, unless there is a short inside. (I once repaired a high end tape recorder with a short inside the meter.)

I am not familiar with that radio so I don't know if there is a meter switch. Probably is. Does it read backwards in all switch positions? Has the meter been disconnected and possibly reconnected backwards?


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 1:46 am 
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Joined: Jan Tue 07, 2020 1:41 am
Posts: 3567
Location: Fenton, MI 48430
Ugctheaters wrote:
I want to thank everyone for putting up with my nerves ending Viking Issue.
The update is NO more fuse blowing, the bad news my meter isn’t working it’s all the way over to the left. Any way to check the meter?

With all the different positions it is likely the meter itself is bad or a connection from the switch to meter is disconnected. I assume the Viking II is producing HV. Meter is specified as a 5ma movement with what appears to be a built-in 20 ohm shunt. Test the meter with a 1.5 volt battery. If the meter is bad, buy same size 5ma movement meter and transfer the internal scale. 5ma movement is rare, you could buy a 1ma movement and change the shunt to 4 ohms.

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Last edited by jimbenedict on Nov Wed 18, 2020 2:03 am, edited 1 time in total.

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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 1:51 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
The meter was disconnected but I already tried swapping the Leads and no change it looks like the needle may be stuck as I can’t even adjust it from the outside. Will pull out tomorrow and try the battery on it


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 2:13 am 
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Joined: May Thu 17, 2018 12:16 am
Posts: 96
Location: Edmonds, WA USA
What did you do to stop the fuse blowing?

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W7VM

Real Radios Glow in the Dark


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 2:27 am 
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Joined: Jun Sun 19, 2011 2:31 pm
Posts: 7694
I have seen paint flaking from the scale that causes the meter to stick on other Johnson gear so that is a possibility. It is also possible that a hard hit caused a pivot point to jump out of its bearing, this is repairable but be VERY careful if you have never done this before because if you bend the clock springs which provide proper tension (and carry current to the meter) you will never get them right again. Sometimes debris will get between the meter coil and the pole piece wedging it, this again is something that can be removed but do so with great care.

I wouldn't directly test any meter movement with a battery, you want something to current limit it in case the movement isn't what you suspect (different coil rating, loose connection to an internal shunt, etc.). There are a number of sites on the web that describe ways to safely test a meter and also measure its internal resistance and full scale current ratings without danger to the movement. My father was very good at rebuilding meter movements, I only inherited a very small portion of his abilities so my goal is to not do anything that requires major repair to a movement!

http://www.bbtvtestequipment.com/testing-a-panel-meter

Rodger WQ9E


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 3:01 am 
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Joined: Jan Tue 07, 2020 1:41 am
Posts: 3567
Location: Fenton, MI 48430
1.5 volt battery would 'hit' the meter hard. Use an ohm meter. It should deflect both the ohm meter and Johnson meter.

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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 4:24 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
Great guys thanks for the info!
To touch on the short I discovered a tube shield that was touching the HV at L21. I lost the short after removing the shield, KISS, keep it simple silly was my lesson! Well at least the entire radio wiring and components were gone over.
I only powered on for a short period maybe 3-4 seconds due to not having a good meter.


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 4:30 am 
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Joined: Jan Tue 07, 2020 1:41 am
Posts: 3567
Location: Fenton, MI 48430
Ugctheaters wrote:
Great guys thanks for the info!
To touch on the short I discovered a tube shield that was touching the HV at L21. I lost the short after removing the shield, KISS, keep it simple silly was my lesson! Well at least the entire radio wiring and components were gone over.
I only powered on for a short period maybe 3-4 seconds due to not having a good meter.

I seen a few Viking II and own one Viking II. Every one had that tube shield removed.

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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 5:18 am 
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The socket used in the Viking II for the bias rectifier accepts a shield but it was never meant to have one installed. The original parts lists shows only four shields, three short and one tall. The short shields go on the two low level audio tubes (V1 and V2) and oscillator tube V5. The tall shield goes on multiplier/driver V6.

The Viking 1 didn't use a shield for the bias rectifier tube either because none is needed but at least there was clearance for one in it with its single 4D32 final. The Viking 2 with its twin 6146 final pushes the plate choke very close to the bias rectifier and a shield definitely can be a problem because of the tight fit.

Rodger WQ9E


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 5:28 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
Ya I can understand why that shield isn’t needed now!
If I hook my multimeter to the back of the meter would I be able to read the mA or do I need to take the original meter out of line to use it?


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 5:39 am 
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Joined: Jan Tue 07, 2020 1:41 am
Posts: 3567
Location: Fenton, MI 48430
Ugctheaters wrote:
Ya I can understand why that shield isn’t needed now!
If I hook my multimeter to the back of the meter would I be able to read the mA or do I need to take the original meter out of line to use it?

Place switch in off position. Place your ohm meter in the diode check position to increase the voltage. Connect the red lead to right and black to left facing the meter. Meter will read about 1/4 scale.

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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 9:02 pm 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
Tried hooking the meter up as a diode checker and showed nothing. Pulled meter cleaned and movement seems ok and resistor wire inside isn’t broken.
I shot a short video using a power supply and 100ohm resister inline .


https://youtu.be/bOriTK3cKjg


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Wed 18, 2020 11:56 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 3659
Location: Seattle WA US
Check your clip leads. Many imported alligator clip leads have poorly soldered or just crimped connections between the lead and the clip. This could cause the wild intermittent indications on your meter as seen in your video.
-Chuck


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 12:06 am 
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Joined: Jun Sun 19, 2011 2:31 pm
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The Viking 2 uses shunts designed for 100 mv full scale reading so it is designed for only a 100 mv drop across the meter for a full scale reading. If you are applying 6 volts across the terminals nothing good is going to happen to that meter movement. It is probably dancing rapidly because it is bouncing off the stops.

Check the link I sent earlier about how to test meter movements. Your 100 ohm resistor in series with this meter and a 6 volt supply is providing 10 times it rated full scare current through the meter. Stop before you destroy the movement if it isn't already damaged.

Rodger WQ9E


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 12:17 am 
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Joined: Jan Tue 07, 2020 1:41 am
Posts: 3567
Location: Fenton, MI 48430
Ugctheaters wrote:
Tried hooking the meter up as a diode checker and showed nothing. Pulled meter cleaned and movement seems ok and resistor wire inside isn’t broken.
I shot a short video using a power supply and 100ohm resister inline .


https://youtu.be/bOriTK3cKjg

My meter showed 1/4 scale with diode checker on VOM.

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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 12:54 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
The link that rsingl is the way I tested per test 2. I just switched it over to Vdc to see what was going on.
Is there a way to check and see if I’m getting the correct current to the meter leads while meter is out? Test with uA meter maybe?


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 1:32 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
I’m going to say the meter is shot.
I hooked up my mA meter on my multimeter and only see Oscillator Current? Took another quick video it’s just easier for me.

https://youtu.be/Vja_GVDo6M8


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 2:14 am 
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Joined: May Thu 17, 2018 12:16 am
Posts: 96
Location: Edmonds, WA USA
Your earlier video shows the meter working fine although being abused with the 6 volt supply as in the video narrative. In the latest video your audio doesn't match the video and you are transposing Buffer and Oscillator controls until the very end when you do rotate the buffer knob. Why do think the meter is "shot" when it worked with 6 volts and a resistor?

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W7VM

Real Radios Glow in the Dark


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 Post subject: Re: Johnson Viking II Issue
PostPosted: Nov Thu 19, 2020 3:03 am 
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Joined: Mar Wed 27, 2019 1:56 am
Posts: 246
Location: Mountainside, NJ
I hooked the original meter back up and it doesn’t move at all so I tried the multimeter and I’m seeing 5mA so I’m figuring the original meter is no good.
When I tune I put in OSC to see I have current on my crystal, then go to Buffer and use Oscillator knob to peak, then go to GRID and use buffer to peak, then Plate, HV on and dip meter with Final knob.
I’m not seeing anything when I go to buffer or grid on the meter?


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