This problem could stem from several causes and, given the information supplied, it is not possible to determine which one is the problem. This answer assumes that you can receive these channels properly with the cable or antenna plugged directly into the television, without being routed through the VCR. When a video signal is absent, many televisions and VCRs blank the screen or display a solid colour, often blue, to avoid displaying snow. The appearance of a blue screen means there is no video signal, either at the input to the VCR or the television. You need to check the signal source in the VCR setup menu. There are usually two choices: antenna or cable. If you have cable television service, the input should be set to cable. If you are using an antenna, it should be set to antenna. Except for channels 2 through 13, the frequencies assigned to the channels on-air and over cable are different. Cable channel 36, for example, does use the same broadcast frequency as UHF channel 36. Assuming that everything appears to be set up and connected properly, I would use a second VCR to see if the problem repeats with it. If the same problem is encountered, then there is likely something wrong with your video feed (or with the configuration of the two VCRs). If the problem goes away, then it is safe to assume it is a problem with the VCR. If everything works properly when the video feed is run directly to the television and the VCR inputs are set properly (cable, antenna), there are a few possibilities: - The tuner or another section of the VCR, such as the video input stage, is defective. The VCR would need to be repaired or replaced. - The VCR is not receiving a strong enough signal. This could be caused by signal losses in the cabling somewhere in the system. If the signal level is too low, the video input will blank. The usual solution is to replace or repair the cable and/or any defective connectors. - Alternately, the video input stage in the VCR could require a stronger signal than is available with your feed. This would indicate a design weakness in the VCR or a defect in the input stage. The latter could be repaired, while the former cannot. - You have cable service (analogue), but do not subscribe to these or other channels. Cable companies install notch filters in the line to block channels you do not subscribe to. It is possible this filter is defective or it attenuates the signal outside the notch too much for your VCR. This could indicate a weakness or fault in the VCR, the filter, or both. Many older VCRs, built in the 1970s and 1980s, had a separate tuner for each input channel. You could assign a braodcast channel to any VCR channel you wanted, but you had a limited number of (preset) channels available on the VCR. The VCR channels were tuned individually to match a broadcast or cable frequency. This tuning can drift over time and you might need to retune some or all of the channels.