Replacement bulb for obsolete Panasonic lantern

[creakndale]

I have an obsolete Panasonic Incandescent Lantern, model EY3793, powered by a 15.6V 13-cell NiMH battery pack. The bulb just burned out
but luckily there was a spare bulb contained inside the unit. Stamped on the bulb is: National 7.2V 0.75A. The manual indicates it's a Xenon bulb with brightness at ~5000 lx. It uses a standard Flanged Base, 0.36" diameter bulb.

The lantern has some smarts to it as it automatically shuts off when the battery back reachs a certain voltage to protect the cells from discharging too far.

So far I have been unable to find any replacement bulbs for this unit. Maybe a Maglite 5-cell Xenon would be a close match? I haven't been able to locate the voltage and current specs of the maglite replacement bulbs, only lumens is specified.

creakndale

 

[Juggernaut]

Ya that's what I'd use. Though if 6vot = 4.85bolt bulb I'd think the 7.5 volt Mag 5-D's bulb would be 6.35 volts so to get 7.2 the 9 volt 6-D light probably uses a 7.85 volt bulb which would be under driven so I'm not sure which one would work now that I think about it:thinking:, though that light must be pretty bright.

:welcome:

 

[nikon]

Yep, it's the standard Mag 6 cell bulb or generic equivalent.

 

[creakndale]

Thanks for your responses!

Today, I took a scope picture of the voltage waveform produced by this little Panasonic lantern. It produces a 38.8Khz sawtooth waveform with a scope measured Mean = 6.9V (Cyc RMS = 7.4V). The RMS current draw is 0.68A via multimeter. Can't figure out how to attach the 83KB waveform pic.

The light output seems fairly bright and the OEM bulb does last a long time. It took over 4 years of my intermittent use before the 1st bulb died.

So as a theoretical comparison to the OEM 7.2V Xenon, the Maglite 5-cell bulb would probably be brighter but burn out quicker? The Maglite 6-cell bulb would be dimmer but last longer?

creakndale

 

[Juggernaut]

Thanks for your responses!

Today, I took a scope picture of the voltage waveform produced by this little Panasonic lantern. It produces a 38.8Khz sawtooth waveform with a scope measured Mean = 6.9V (Cyc RMS = 7.4V). The RMS current draw is 0.68A via multimeter. Can't figure out how to attach the 83KB waveform pic.

The light output seems fairly bright and the OEM bulb does last a long time. It took over 4 years of my intermittent use before the 1st bulb died.

So as a theoretical comparison to the OEM 7.2V Xenon, the Maglite 5-cell bulb would probably be brighter but burn out quicker? The Maglite 6-cell bulb would be dimmer but last longer?

creakndale

That sounds about right to me.

 

[ampdude]

I don't think the xenon version would last very long, but you might get a useable life out of the 5 cell krypton.

 

[Nubo]

KPR118?

or Gk7270

http://reflectalite.com/kryptonpage.html

 

[PPPK68]

Have you tried a new bulb yet? Thoughts?
I have the exact same situation. Love my Panasonic lantern! Got 7 years from the orig.two bulbs.

 

[creakndale]

Great information from a terrific forum of bright people!

Running some more experiments, I set the Panasonic Lantern at 36" from a white wall. The main bright spot of the OEM Xenon bulb is a decent circle of 7" diameter.

The other day, I picked up a KPR118 (Krypton bulb, 7.2V, 0.6A) from Radio Shack, Catalog # 272-1163. This bulb is of similar brightness but the bright spot is about 1/2 the size with an oval of 3" x 4".

I also ordered a Maglite Mag-Num Star Xenon bulb for 6-Cell C & D flashlights from eBay seller: "Ecop Police Supply" and it arrived today. This bulb produces less brightness in a fair shaped circle with a bright spot of 5" diameter.

Both of these bulbs are acceptable in the Panasonic EY3793 Lantern but fall short of the OEM 7.2V, 0.75A Xenon bulb.

Based on the recommendations from CandlePower forum members, I could still try the following:
1) Maglite Mag-Num Star Krypton (or possibly Xenon) bulb for 5-Cell C & D flashlights
2) Krypton GK7270 7.2V, 0.7A from Reflectalite.com

Four years ago I ordered a couple of bulbs from Reflectalite (located in Britain) for a friends bicycle light. The bulbs arrived quickly and without any shipping issues so I plan to order their Krypton GK7270 (due to similar specifications to the OEM Xenon) and give it a try.

creakndale

 

[creakndale]

*** Flash ***
I just found the Panasonic Parts and Accessories web page for the EY3793 Lantern. It appears the OEM 7.2V, 0.75A Xenon bulb is still available.

The replacement 7.2V, 0.75A Xenon part number is: EYMB-72P75X
It's sold as a 2 bulb pack for $6.98 with $5.25 S&H plus some tax.

Go to:
http://www.pasc.panasonic.com/Epartr/PartslistChoice.asp?
Search by Part Number or Model Number

I ordered a pack of 2 bulbs just moments ago. They ship from Kent, Washington.

I also stumbled across the Service Manual, Parts Breakdown for this Lantern:
http://www.panasonic.com/consumer_electronics/bp_cordless_tools/pdf/EY3793.pdf

creakndale

 

[lctorana]

Today, I took a scope picture of the voltage waveform produced by this little Panasonic lantern. It produces a 38.8Khz sawtooth waveform with a scope measured Mean = 6.9V (Cyc RMS = 7.4V). The RMS current draw is 0.68A via multimeter. Can't figure out how to attach the 83KB waveform pic.

The light output seems fairly bright and the OEM bulb does last a long time.

Mag-Num Star Xenon bulb for 6-Cell C & D flashlights... ...produces less brightness...

Fascinating. Many of the answers in this thread have been predicated on the normal flashlight concept of steady DC voltage into a bulb, where higher-current bulbs, such as the 6-cell MagXenon (7.6V 0.77A), will be brighter.

Now you quote 7.4Vrms - I assume that is under the load of your OEM 7.2V 0.75A globe? If so, the 6-cell MagXenon will be a smidgin underdriven. The 6-cell Mag Krypton (7.5V 0.7A) will be almost a perfect match for your OEM bulb and might be worth a try.

You could also try, as you suggest yourself, a 5-cell MagXenon (6.3V 0.77A), which, being rated to run on 5 alkaline batteries, must be able to (briefly) cope with 7.5V, so should survive the 7.4Vrms of your lantern.

You can try the KPR118 (7.2V 0.75A, krypton), which is a perfect electrical match, but a bit down on lumens, or a HPX60 (7.2V 0.85, Xenon) which will be ideal if the inverter can supply the extra 100mA.

 

[creakndale]

Yes, lctorana. the 7.4Vrms scope measurement was while driving the OEM 7.2V 0.75A bulb.

Today, I received the replacement Xenon bulbs from Panasonic in Kent, Washington. It took seven days from internet purchase to UPS delivery. Stamped on the bulbs is, "Panasonic 7.2V 0.75A XE JAPAN". I tried them both in the lantern. One bulb outputs the same 7" circle pattern with the lantern at 36" from a white wall. The other bulb outputs a slightly larger 8" circle pattern. Both appear to be the same brightness as the OEM Xenon bulb.

creakndale