Ever since the transition to over the air digital TV, I can not receive these two stations using the digital converter box.
I recall hearing something about switching from UHF to VHF (or was it the other way around?), but I don’t understand why that would affect reception. I used the box prior to the absolutely last, final, cutover date, and both those stations were coming in fine. Now Channel 4, all three versions, another major network affiliate comes in fine, but not 7 or 9.
Is this another scheme to make us buy more ‘stuff’?
I don’t live in DC, but I may be able to help. Try this: unplug the antenna from the converter box. Get it to scan. It won’t find anything, but it will purge the old channel assignments from before. Now, reconnect your antenna and scan again. Chances are it will find the channels in their new positions.
The only full power channels on VHF in Washington are WJLA - 7 and WUSA - 9
The problem you’re having likely stems from the use of virtual channels.
For instance in WRC-TV is actually on Channel 48 and WTTG is actually on Channel 36 but do to PSIP which is a standard for virtual channels (and other things), when you hit Channel 4 in your TV it comes up as WRC-TV. The TV is actually, in reality turning to channel 48 but your tuner shows Channel 4
The stations lobbied for this because they didn’t want to rebrand.
Before the transition WUSA was on channel 34 and WJLA was on channel 39.
After the transition to digital WUSA and WJLA elected to move back to their VHF channels. Now you may ask why didn’t WRC (4) and WTTG (5) do this?
Mainly because the low VHF channels (2-6) are subject to a lot of interference. VHF is VERY cheap to operate. UHF not so.
For instance, WJLA on channel 7 broadcasts with 30 kw. When it was on Channel 39 it used 646 kw. That’s mean the electric bill will be 21 times LESS on channel 7
VHF frequencies require less power. So if you can go back it’s preferable. WJLA is operating a low power TV still on analog, on Channel 49. (low power TV isn’t required to go digital yet, but they may if they wish)