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THE AM BULLETIN BOARD => Technical Forum => Topic started by: W3MMR on June 10, 2019, 09:46:32 PM



Title: Replacement DX-100 bulbs
Post by: W3MMR on June 10, 2019, 09:46:32 PM
Looking for replacement bulbs for the 100. The VFO and meter lamps. Anyone try LED replacements? The book doesn't say much as far as wattage or anything as far as the orginals go. They look jist like automotive bulbs. Anyway, i would like as bright as i can get. Thanks in advance

Perry
W3MMR


Title: Re: Replacement DX-100 bulbs
Post by: kb3rdt on June 10, 2019, 11:57:17 PM
if you want look original get the amber.

I use them in my NC-300 receiver they been in there for 5 years now!


Title: Re: Replacement DX-100 bulbs
Post by: KK4YY on June 11, 2019, 07:12:06 AM
Perry,

I believe the original bulbs for the meter and frequency display are #44. They're 6 volt bulbs so you may not find an automotive LED that would work. If you want a lifetime supply, check this out.

https://www.ebay.com/itm/44-Miniature-Lamp-3-pak-Three-Boxes-of-44-bulbs-30-Bulbs-Total/142718328221?


Don


Title: Re: Replacement DX-100 bulbs
Post by: w4bfs on June 11, 2019, 07:53:48 AM
I am replacing all incadescent pilot lamps with leds .... less waste heat .... a variety of types colors and end fire or side fire available .... much longer life


Title: Re: Replacement DX-100 bulbs
Post by: W3MMR on June 11, 2019, 11:43:44 AM
Thanks guys. I ended up ordering a pack of 12 6.3v LED replacements for pinball machines. I got the white ones as opposed to the warm white because me personally, i like the ultra white look. Bur if I dont like it, i may just orders those ones you recommended Don. Thats a hell of a deal.

Perry
W3MMR


Title: Re: Replacement DX-100 bulbs
Post by: kb3rdt on June 11, 2019, 11:46:24 AM

here is a 6.3 volt replacement

https://www.superbrightleds.com/moreinfo/panel-indicator-lights/ba9s-led-landscape-light-bulb-1-led-ba9s-retrofit-5-lumens/2539/


Title: Re: Replacement DX-100 bulbs
Post by: Opcom on June 11, 2019, 08:36:43 PM
Tending  to like LEDs here too. They don't continue to cook the dial scales, meters, etc. I used to worry about UV froom white ones but I think the concern was unfounded. Anyway they sure beat lamps for lifespan when it comes to removing heavy gear from racks.


Title: Re: Replacement DX-100 bulbs
Post by: W3MMR on June 12, 2019, 09:48:10 AM

here is a 6.3 volt replacement

https://www.superbrightleds.com/moreinfo/panel-indicator-lights/ba9s-led-landscape-light-bulb-1-led-ba9s-retrofit-5-lumens/2539/

Those look just like the ones I ordered from Amazon! Good deal.


Title: Re: Replacement DX-100 bulbs
Post by: W2PFY on June 12, 2019, 10:30:20 PM
The high voltage indicator lamp is rated at 3 watts at 110 vols per the manual. I have looked at that lamp placement and its a very difficult job to replace it. It seems to me that the front panel would have to be removed to get to it? Anyhow, I had one ok DX 100 and a parts unit. I donated them to KF2VM as he was looking for the particular radios that I had that came from a well known ham from NJ. I have so many projects that I felt that giving them to Jamie would be the best bet for them ever getting on the air. Back to the HV light, if ever there was a place for an LED, that is where I was going to install one. 
Attached is a very clean copy of the DX-100 manual for those who may want to download it.


Terry


Title: Re: Replacement DX-100 bulbs
Post by: KK4YY on June 13, 2019, 02:25:37 AM
Terry,

That 110V 3W bulb can be replaced using a long, flexible, properly sized, tube or hose to grab and unscrew the old bulb and install a new one. Cake.


Don


Title: Re: Replacement DX-100 bulbs
Post by: W3MMR on June 13, 2019, 06:30:33 AM
Terry,
Yes, i always wondered how the hell to get to that bulb, but Don just had the idea! I head of guys using a large LED as a replacement for that bulb.


Title: Re: Replacement DX-100 bulbs
Post by: W2PFY on June 13, 2019, 06:13:22 PM
Another thought I had inasmuch as 6146 tubes are not cheap is use the 12 volt version in place of them. They are way cheaper on the Bay.  It would be real easy to do. From memory you would just lift the center tap of the filament transformer then ground one side of the filament transformer. Ground one side of the 1625 tubes. Not much to it? Make sure the 12 volt version of the 6146 tubes are on the 12 volt side of the transformer. If you want to get real fancy put a bridge rectifier on the 12 volt output with a big fat filter cap for 12 vdc. Now you have some bragging rights! I didn't provide the model number of the 12 volt versions because there are many different types.

Put a note in the DX 100 explain that 6146 tubes are not in use otherwise, a new owner may wonder why they look so bright and won't last long!

I didn't do it, do you think it will work?

Terry


Title: Re: Replacement DX-100 bulbs
Post by: KK4YY on June 13, 2019, 06:31:57 PM
Another thought I had inasmuch as 6146 tubes are not cheap is use the 12 volt version in place of them. They are way cheaper on the Bay.  It would be real easy to do. From memory you would just lift the center tap of the filament transformer then ground one side of the filament transformer. Ground one side of the 1625 tubes. Not much to it? Make sure the 12 volt version of the 6146 tubes are on the 12 volt side of the transformer. If you want to get real fancy put a bridge rectifier on the 12 volt output with a big fat filter cap for 12 vdc. Now you have some bragging rights! I didn't provide the model number of the 12 volt versions because there are many different types.

Put a note in the DX 100 explain that 6146 tubes are not in use otherwise, a new owner may wonder why they look so bright and won't last long!

I didn't do it, do you think it will work?

Terry

Been there, done that.

I use 8552 or 6883B tubes in my DX-100. Both are 12V versions of the 6146B. I rewired the sockets and labeled them. I left the c.t. of the filiment transformer grounded and have a seperate transformer for the 6DQ5 modulator tubes (which replaced the 1625's).

Remember to make sure the filament load is balanced when making any changes like this. There are a few tricks you can use. The 12BY7's  and 12AX7 can be wired for 6 or 12 volts, The 6AU6 and 6AQ5 tubes can be replaced with 12AU6 and 12AQ5 tubes, when wired correctly.


Don


Title: Re: Replacement DX-100 bulbs
Post by: W2PFY on June 14, 2019, 02:33:05 PM
Quote
Remember to make sure the filament load is balanced when making any changes like this. There are a few tricks you can use. The 12BY7's  and 12AX7 can be wired for 6 or 12 volts, The 6AU6 and 6AQ5 tubes can be replaced with 12AU6 and 12AQ5 tubes, when wired correctly.

Hey Don, you know I never gave this a thought? I wonder at what stage had I actually made the changes, would I have done anything before blowing out some tubes with 12 volts?

At some point if I ever run across a very clean DX-100 for cheap money, I may do what you have done. Your rig when I fist heard it, I said to myself,is that another SDR set? It sounds great!

The late K1DEU John,also used sweep tubes but he used four tubes with high voltage filaments all in series ruining right off the ac line voltage. I don't recall the tube types? He sounded like a million bucks with his deep voice on the rig. I looked for his old website but could not find it to see what the tubes were?


Title: Re: Replacement DX-100 bulbs
Post by: KK4YY on June 14, 2019, 04:20:02 PM
Terry,

As I recall, John used 6LW6's. But I guess they were 36LW6's if he had the filaments in series... a pair modulated by a pair.

And thanks for the kind words. :)


Don

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