I recently aquired a Zenith H500 Transoceanic which I got up and running on all bands. I turned it off one day and turned it back on the next day and now all it has is the Broadcast band and 4 to 8 Mhz. Other bands are very weak and only receive a couple of strong stations. There is 1.55 volts across the 1L6. The 1L6 tests in the middle of the Good area. Does it sound like the 1L6 has gone south? The band switches appear to be to be OK.

Hope not, these are very scarce, read expensive. I remember a thread about possibly modification to use 1R5, which is not as good especially on the higher bands. If you recapped the set, and replaced any out of spec resistors and cleaned all the switches and tube sockets, check voltages to see if there is a problem somewhere down the line.

:I recently aquired a Zenith H500 Transoceanic which I got up and running on all bands. I turned it off one day and turned it back on the next day and now all it has is the Broadcast band and 4 to 8 Mhz. Other bands are very weak and only receive a couple of strong stations. There is 1.55 volts across the 1L6. The 1L6 tests in the middle of the Good area. Does it sound like the 1L6 has gone south? The band switches appear to be to be OK.
:

What time of day are you listening?

The low bands (below 10 MHz.) will be best at night. The higher bands are extremely variable due to sunspots and usually best during the day.

Rich

:Hope not, these are very scarce, read expensive. I remember a thread about possibly modification to use 1R5, which is not as good especially on the higher bands. If you recapped the set, and replaced any out of spec resistors and cleaned all the switches and tube sockets, check voltages to see if there is a problem somewhere down the line.
:
::I recently aquired a Zenith H500 Transoceanic which I got up and running on all bands. I turned it off one day and turned it back on the next day and now all it has is the Broadcast band and 4 to 8 Mhz. Other bands are very weak and only receive a couple of strong stations. There is 1.55 volts across the 1L6. The 1L6 tests in the middle of the Good area. Does it sound like the 1L6 has gone south? The band switches appear to be to be OK.
::
:
:

Hello:

I would let the unit "burn in" for a few weeks. In other words, I would turn the unit on and let it run for an hour or so a day. This would help to ferret out dirty band switches, help to reform some coupling caps ( remember they have not seen any B+ for quite a long time!! ) and see if this helps to improve performance. Also it IS possible that you have developed a short in one of the tubes. A GENTLE rap on each with the rubber eraser of a pencil with the unit operating may show this. You also could have dirty tube sockets. I recommend removing each tube and using a good quality contact spray on the sockets prior to removal and reinsertion of the tubes.

I have a portable AM radio , post - 1940s that has the usual tube lineup ( 1U4, 1U5, 3V4, 1R5 I believe), The unit would sometimes stop running due to a loss of the onboard local oscillator. Cleaning the socket of the tube responsible for the LO did the trick!!

Lou

:What time of day are you listening?
:
:The low bands (below 10 MHz.) will be best at night. The higher bands are extremely variable due to sunspots and usually best during the day.
:
:Rich
:
::Hope not, these are very scarce, read expensive. I remember a thread about possibly modification to use 1R5, which is not as good especially on the higher bands. If you recapped the set, and replaced any out of spec resistors and cleaned all the switches and tube sockets, check voltages to see if there is a problem somewhere down the line.
::
:::I recently aquired a Zenith H500 Transoceanic which I got up and running on all bands. I turned it off one day and turned it back on the next day and now all it has is the Broadcast band and 4 to 8 Mhz. Other bands are very weak and only receive a couple of strong stations. There is 1.55 volts across the 1L6. The 1L6 tests in the middle of the Good area. Does it sound like the 1L6 has gone south? The band switches appear to be to be OK.
:::
::
::
:
:

and remember NOT to pull any tubes out while the radio is on, or you could burn out the filaments on the rest of the 1 volt tubes!